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Motivated by the recently discovered nonlinear dynamics of cavity–magnon polaritons (CMPs), bistable CMP behavior is investigated theoretically in the case of two yttrium iron garnet (YIG) spheres (YIG1 and YIG2) in a microwave cavity, which is induced by the magnon Kerr effect of YIG1 originating from the magnetocrystalline anisotropy. The bistability appears in the form of sharp CMP frequency switching. More importantly, when the driving field acts on YIG1 and drives the magnon dark mode, the nonlinear Kerr effect at high excitation plays an important role in creating frequency detuning between the two YIG spheres. This results in sharply vanishing destructive interference between two YIG spheres and simultaneously makes the invisible magnon dark mode visible. However, when the driving field acts on the cavity, the magnon dark mode remains dark and there is no bistability in the CMPs when the driving frequency is tuned to the magnon dark mode, this being because the excitation energy cannot be transferred from cavity to magnon. The present research provides a promising approach for information storage and processing in multimode systems under high excitation. [ABSTRACT FROM AUTHOR]

Inspired by the new discovery that the nonlinear dynamics of the cavity magnon polaritons have been observed with a small yttrium iron garnet (YIG) sphere (which introduces a nonlinear Kerr effect) placed into a microwave cavity, we theoretically study the nonlinear behaviors of the magnon dark mode without the magnon Kerr effect by inserting two YIG spheres into a microwave cavity under the strong driving field. The resulting bistability features of the magnon dark mode are sensitive to the frequency detuning between two YIGs and the magnetic field. Especially, when two YIGs have a finite frequency detuning, the magnon dark mode at the cavity resonance frequency does not display bistability. Our research not only sheds light on the nonlinear effect of the magnon dark mode in a strong driving field but also provides a theoretical basis for the application in information storage and novel spintronics. [ABSTRACT FROM AUTHOR]

In this paper, a vehicle forced Jane change behavior detection algorithm based on machine learning is proposed. Collect the vehicle's forward looking monocular video image and determine the reasonable region of interest; The intention and process of vehicle forced lane change are analyzed by video image features, and the vehicle forced lane change motivation model is established; Use Kalman filter in machine learning to track vehicles; Calculate the centroid coordinates of the target vehicle and the distance of the lane line, and determine whether the vehicle in front has a forced lane change behavior in combination with the lane change motivation model. The experimental results show that this method has higher accuracy in detecting vehicle lane change behavior. [ABSTRACT FROM AUTHOR]

In order to improve the traffic capacity of the intersection and shorten the traffic delay, a new urban intelligent traffic signal coordination control system based on machine learning is proposed in this paper. The hardware of the system is designed, including annunciator, vehicle detection module, traffic flow statistics module and signal control module. The reinforcement learning algorithm in machine learning is used to train and learn the traffic vehicle data, so as to extract the spatial characteristics of the traffic environment state. Under the constraint of the minimum loss function, the training objective is solved and the output result of the optimal coordinated control of traffic signals is output. The experimental results show that compared with the traditional control system, the maximum traffic capacity of the intersection under the control of this system is 2400 vehicles/hour, and the maximum traffic delay is no more than 30s. [ABSTRACT FROM AUTHOR]

An experimental comparative study of the detonation re-initiation downstream of an orifice plate and the typical deflagration-to-detonation transition in a smooth tube is carried out. In this study, two tube configurations are employed to study the onset of detonation in stoichiometric methane–oxygen mixtures, i.e., a smooth tube and a tube with a single orifice plate placed in the entrance of the self-sustained detonation transmission. Combustion wave velocity measurement and soot-foil visualization are used to characterize the initiation of detonation. The dimensionless parameters correlated with cell size, tube diameter, and orifice diameter are introduced to analyze the detonation initiation process. The results indicate that the dependence of the detonation initiation distance on the initial pressure as a whole is close to inverse proportionality, and the fitting degree is higher for the detonation re-initiation downstream of the orifice plate. The effect of inherent instability of CH 4 –2O 2 on the onset of detonation is significantly enhanced when the cell size is smaller than the characteristic dimension of an unobstructed tube, either for deflagration-to-detonation transition in a smooth tube or for the detonation re-initiation downstream of an orifice plate. [ABSTRACT FROM AUTHOR]

Oxalic acid (OA) is a crucial pathogenic factor for Sclerotinia spp. fungi, which is closely related to Botrytis spp. fungi. Whether OA is a pathogenic factor for the causal agent of grey mould in lily, Botrytis elliptica, and the response of lily to OA are poorly understood.To address these questions, lesion tissues and deposition of calcium oxalate (CaOX) and callose were observed in diploid and tetraploid leaves of L. rosthornii after inoculation with B. elliptica. Oxalate oxidase (OXO) activity and the transcript levels of some genes related to OA degradation (LrGLP1, LrGLP2 and LrWRKY4), reactive oxygen species (ROS) production/scavenging systems (LrRBOHD, LrGST, LrPOD and LrAPX1) and pathogen‐related protein (PR) synthesis (LrCHI, LrBGL and LrPR10) were compared.After diploid and tetraploid leaves inoculation, lesion tissue and callose and CaOX were separately observed around in guard cells and stomata rather than the epidermis in the infected area. OXO activity was triggered at 2 h post‐inoculation (hpi) in both ploidy leaves, and it was higher in the latter from 12‐48 hpi. Expression of LrGLP1, LrGLP2, LrRBOHD, LrGST, LrPOD, LrCHI, LrBGL and LrPR10 was higher in tetraploids than in diploids from 24(12)–36(48) hpi.In conclusion, for B. elliptica, OA mainly chelates Ca2+ from the stomata cell wall. The strong capability to degrade OA and higher expression levels of some genes related to ROS accumulation/scavenging and PR synthesis may partially explain the relatively higher grey mould resistance of tetraploid L. rosthornii. [ABSTRACT FROM AUTHOR]

In this study, Zr0.5Hf0.5O2 films were fabricated on Si substrate and were annealed at different temperatures by rapid thermal annealing (RTA) process. The charge trapping memory devices based on Zr0.5Hf0.5O2/SiO2/Si simple structure were investigated in detail. The memory device annealing at 690 °C shows the best property with a memory window of 5.6V under ±12V sweeping voltages in its capacitance-voltage curve and a better retention property. The high resolved transmission electron microscopy shows the generated SiO2 working as tunneling layer after RTA process, whose thickness increases with the rise of temperature. Combined with the TEM results, the photoluminescence spectrum and in situ angle resolved photoemission spectroscopy results further verify that oxygen vacancies and inter-diffusion layer also play a crucial role in charge trapping performance. This work provides direct insights for the charge trapping mechanisms based on high-k Zr0.5Hf0.5O2 films devices. [ABSTRACT FROM AUTHOR]

Neoclassical offset rotation induced by non-axisymmetric magnetic perturbations in tokamaks is investigated using NTVTOK model based on plasma profiles in one DIII-D discharge. The calculated counter-Ip (Ip indicates plasma current) ion root of neoclassical offset rotation is found to be consistent with DIII-D experimental observations. The modeling results predict that this DIII-D plasma regime is close to the marginal condition for the co-Ip electron root to exist. The importance of bounce–drift resonance is highlighted in the calculation, which affects the neoclassical offset rotation, especially the electron root. The ion root usually exists for various parameter regimes, while the electron root is only possible in low collisionality (e.g., high temperature and/or low density) regimes. The magnetic perturbation spectrum is found to influence the existence of electron roots when electrons are closer to resonant superbanana plateau regime than ions. By adjusting the plasma collisionality and tuning the spectrum of magnetic perturbations, it is possible to control the plasma rotation and hence to optimize the plasma confinement. [ABSTRACT FROM AUTHOR]

We analyze six cases of magnetic reconnection with large separatrix angles and separatrix jets observed on the solar disk. The separatrix angle is defined as the angle between the two separatrices on the two sides of the outflow region. The plasma jets are observed immediately downstream of the separatrices. The morphological characteristics and magnetic field configurations of all magnetic reconnections are displayed. At the same time, we calculate several physical parameters of each case, which include the inflow velocity (from 2.3 to 24 km s−1), the outflow velocity (from 1.9 to 43 km s−1), the separatrix jet velocity (from 13 to 82 km s−1), the width (from 0.42 × 103 to 1.2 × 103 km) and length (from 1.4 × 103 to 4.3 × 103 km) of the current sheet, and the separatrix angle θsep (from 72° to 128°). We find that the outflow velocity, the separatrix jet velocity, and the width and length of the current sheet are positively related to the inflow velocity, but the separatrix angle does not depend on the inflow velocity and it is related to the initial magnetic field configuration before magnetic reconnection. Meanwhile, the velocities of the outflow and the separatrix jet decrease with increasing , indicating that when the separatrix angle is close to 90°, the jet and the outflow reach their maximum velocities. These observations are compared with the results of the theoretical model and the numerical simulation. [ABSTRACT FROM AUTHOR]

The immiscible polymeric blend of polypropylene (PP) and polyvinyl alcohol (PVA) was manufactured into multifilament fibers via the melt-spinning process, of which the mass ratio of PP to PVA was selected as 30%/70%. The PP micro/nanofibers were accessible with the removal of PVA in hot water. Kaolinite particles were also incorporated to modify the micro/nanofibers surface, for functionalization efficiencies play a useful role with the aid of a high specific surface area. The octahedral layers of kaolinite particles were grafted with a regioselective process by octadecyl (C18H37-) groups modified into Janus particles to better localize the fillers at the biphasic interface. As a result, the kaolinite particles having a Janus morphology are more distributed at the interface of the polymers, as observed by SEM. The knitting structures are capable of being maintained after the selective phase extraction leaving numbers of micro/nanofibers. After the incorporation of kaolinite particles, there are still some amounts of particles appearing on the surface of PP micro/nanofibers. Besides, there is a mechanical enhancement of the knitted fabrics, especially when the Janus particles are used, even after the selective phase extraction, which the conventional chemical treatment cannot bring. This study sets an example of fabricating PP micro/nanofiber fabrics surface-modified and mechanically enhanced using Janus kaolinite particles. [ABSTRACT FROM AUTHOR]

Crystal growth of the glass-forming CuZr alloy is shown to be abnormally slow, which suggests a new method to identify the good glass-forming alloys. The crystal growth of elemental Cu, Pd and binary NiAl, CuZr alloys is systematically studied with the aid of molecular dynamics simulations. The temperature dependence of the growth velocity indicates the different growth mechanisms between the elemental and the alloy systems. The high-speed growth featuring the elemental metals is dominated by the non-activated collision between liquid-like atoms and interface, and the low-speed growth for NiAl and CuZr is determined by the diffusion across the interface. We find that, in contrast to Cu, Pd, and NiAl, a strong stress layering arisen from the density and the local order layering forms in front of the liquid-crystal interface of CuZr alloy, which causes a slow diffusion zone. The formation of the slow diffusion zone suppresses the interface moving, resulting in much small growth velocity of CuZr alloy. We provide a direct evidence of this explanation by applying the compressive stress normal to the interface. The compression is shown to boost the stress layering in CuZr significantly, correspondingly enhancing the slow diffusion zone, and eventually slowing down the crystal growth of CuZr alloy immediately. In contrast, the growth of Cu, Pd, and NiAl is increased by the compression because the low diffusion zones in them are never well developed. [ABSTRACT FROM AUTHOR]

Brown planthopper (BPH), white‐backed planthopper (WBPH) and small brown planthopper (SBPH), are the closely related rice pests that perform differentially on wheat plants. Using fecundity as a fitness measure, we found that SBPH well‐adapted on wheat plants, followed by WBPH, while BPH had the worst performance. The transcriptomic responses of SBPH and BPH to wheat plants have been compared previously. To understand the different fitness mechanisms of three planthoppers, this study first investigated the transcriptomic responses of WBPH to rice and wheat plants. Genes involved in detoxification, transportation and proteasome were significantly enriched in WBPH in response to different diets. Moreover, comparative analysis demonstrated that most co‐regulated genes in BPH and SBPH showed different expression changes; whereas most co‐regulated genes in BPH and WBPH exhibited similar expression changes. Subsequently, this study also investigated the influences of host plants on the bacterial community of three planthoppers. The three planthoppers harboured distant diversity of bacterial communities. However, there was no dramatic change in bacterial diversity or relative abundance in planthoppers colonized on different hosts. This study illustrates generic and species‐specific changes of three rice planthoppers in response to different plants, which deepen our understanding towards the host fitness for planthopper species. [ABSTRACT FROM AUTHOR]

Plasma effects, such as the multi-component kinetic diffusion and self-generated electromagnetic fields, are recognized as a pivotal key to understanding the physics of interface evolution in inertial confinement fusion and supernova remnants. In this work, a two-dimensional hybrid fluid-PIC code is used to investigate the ion kinetic effects of the single-mode Richtmyer–Meshkov instability (RMI) at the interface between hydrogen plasma and carbon plasma. After an electrostatic shockwave passing through the perturbed interface, the RMI, which reshapes the interface, grows via the vorticity depositing as well as the self-generated magnetic field. After scaling the growth of the interfacial mix region with time, the density transition layer has been found to exceed the disturbance wavelength and lead to a suppression of the instability evolution finally. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of sulfate in metatitanic acid on crystal transition and crystal growth of TiO2 during the calcination of metatitanic acid from sulfate process, ammonia was used to remove sulfate in metatitanic acid in this study. TG-DTA, XRD and SEM were used to analyse the crystal phase transition and crystal morphologies. Experiments showed that removal of sulfate will be beneficial to crystal transition and growth. In calcination of desulfurized metatitanic acid, both the solid-state crystallization and the phase transition from anatase to rutile have been advanced by 50°C as compared to the control samples without desulfurization treatment. Moreover, the temperature can be reduced by 60°C to achieve the same rutile conversion rate of 97.6%, and the particle size can be reduced by 70 nm. The reduction in calcination temperature greatly alleviates the sintering tendency of TiO2 and aid to produce TiO2 crystals of even size. [ABSTRACT FROM AUTHOR]

The NaCl-type La monopnictides are proper reference materials for the study of strongly correlated rare-earth pnictides. Yet, despite the simple crystal structure of this system, traditional density functional theory (DFT) calculations have dramatic failures in describing their electronic properties: DFT severely underestimates the band gaps and thus predicts incorrect transport characters of them. Here, we perform a corrected DFT calculation to rectify this failure. Our results show that LaN, LaP, and LaAs are semiconductor with band gaps of 0.82, 0.25, and 0.12 eV, respectively, and LaSb is semimetallic with an overlap of conduction and valence bands approximately 0.28 eV, in agreement with the available experiments. Additionally, under high-pressure, we find that LaN displays a new sequence of phase-transition, B1→anti-B10→B2, which is different from the previous theoretical predictions but consistent with the recent experiment. [ABSTRACT FROM AUTHOR]

Partial blockages commonly exist in water pipelines due to various physical, chemical, and biological processes, including sediment, corrosion, and biofilm. The formed blockages can result in low flowing capacity, additional energy loss, and water quality deterioration during the water conveyance process, such as urban water supply and drainage systems. This paper presents an investigation on the interaction of transient pressure waves with pipe-wall roughness and blockages in water pipelines. The analytical expression of wave propagation in a pipeline with rough blockages is firstly derived by multiscale wave perturbation analysis for transient pipe flows. The analytical results and analysis demonstrate that the wave scattering (amplitude damping and phase shifting) is dependent on the relationship between the incident wavelength and the correlation length of roughness-blockage disorders in the pipeline. The relative importance of pipe-wall roughness friction and pipe blockage constriction to wave scattering in terms of wave envelope attenuation and wave phase change is then investigated based on the analytically derived results. Two dimensionless parameters, which are functions of the properties of incident waves, pipe-wall roughness, blockage severity and range, and internal fluid conditions, are formulated to characterize such relevance and importance. For validation, the analytical results are compared with experimental data collected in this study based on a laboratory experimental test system. Finally, the key results and findings of this study are discussed for their applicability and implication to transient pipe flow modeling and pipeline condition assessment in practical applications. [ABSTRACT FROM AUTHOR]

In this study, a novel integrated fault estimation (FE) and fault-tolerant control (FTC) design approach is developed for a system with time-varying delays and additive fault based on a dynamic event-triggered communication mechanism. The traditional static event-triggered mechanism is modified by adding an internal dynamic variable to increase the inter-event interval and decrease the amount of data transmission. Then, a dynamical observer is designed to estimate both the system state and the unknown fault signal simultaneously. A fault estimation-based FTC approach is then given to remove the effects generated by unknown actuator faults, which guarantees that the faulty closed-loop systems are asymptotical stable with a disturbance attenuation level γ. By theory analysis, the Zeno phenomenon is excluded in this study. Finally, a real aircraft engine example is provided to illustrate the feasibility of the proposed integrated FE and FTC method. [ABSTRACT FROM AUTHOR]

Let A be a sequence of positive integers and P(A) be the set of all integers which are the finite sum of distinct terms of A. Let B = { b 1 < b 2 < ⋯ } be a sequence of positive integers with b 1 ∈ { 4 , 7 , 8 } ∪ [ 11 , + ∞) . By observing the results of Chen and Fang [2], Fang and Fang [4] found that 3 b 1 + 5 is the critical value for b2 such that there exists a sequence A of positive integers for which P (A) = N \ B . For b 2 = 3 b 1 + 5 , they considered the inverse problem and determined the critical value for b3. Also, for b 2 ≥ 3 b 1 + 5 , they asked for the critical value for b3. In this paper, we solve this problem. [ABSTRACT FROM AUTHOR]

Benefiting from the latest experiment of non-linearity in cavity magnon polaritons due to the magnetocrystalline anisotropy in the yttrium iron garnet (YIG) crystal, we theoretically propose a cavity magnonics model that can be used to study the bistable behaviors by changing the coupling strength, which presents the rich and interesting phenomena. In the case of resonance, the critical driving powers of the upper and lower polariton modes have the smaller values for the larger coupling strength but the larger values for the smaller coupling strength. In addition, the upper and lower polariton modes show the repulsive and attractive features, respectively, when the derivative of the coupling strength with respect to the position of the YIG sphere changes from positive to negative. Especially, the bistability of the lower polariton mode disappears when the driving power is strong enough. Our research broadens the means of manipulation of non-linearity in cavity magnon system, which provides a promising application for cavity spintronics and information processing. [ABSTRACT FROM AUTHOR]

The apparent metabolizable energy (AME), AME corrected to zero-nitrogen retention (AMEn), and net energy (NE) values of 2 corn samples both stored for 3 yr were determined in laying hens with reference diet substitution method. Reference diet was formulated according to standard layer requirement, and test diets contained 50% of corn samples and 50% of the reference diet. Fifty-four Hy-Line Brown hens at the age of 36 wk were used. The heat production and energy metabolism of birds were measured in open-circuit respiratory chambers with 6 replicates (3 birds per replicate) per diet in a randomized design. Birds were fed experimental diets for 7 D in the chamber as adaptation. During the following 3 D, feed intake, metabolizable energy value, nitrogen balance, energy balance, egg production, O2 consumption, CO2 production, and energy efficiency were determined. The AME values of corn 1 and corn 2 were 3,485 and 3,675 kcal/kg DM, respectively. The corresponding AMEn values were 3,452 and 3,596 kcal/kg DM, and the NE values were 2,575 and 2,693 kcal/kg DM, respectively. The NE:AME ratios of corn 1 and corn 2 were 74.4 and 73.3%, respectively. The NE:AMEn ratios of corn 1 and corn 2 were 75.0 and 74.9%, respectively. The AME, AMEn, and NE values of the 2 corn samples both stored for 3 yr were lower than the literature values for fresh corn. [ABSTRACT FROM AUTHOR]

This paper is devoted to identify a space-dependent source term in a multi-dimensional time fractional diffusion-wave equation from a part of noisy boundary data. Based on the series expression of solution for the direct problem, we improve the regularity of the weak solution for the direct problem under strong conditions. And we obtain the uniqueness of inverse space-dependent source term problem by the Titchmarsh convolution theorem and the Duhamel principle. Further, we use a non-stationary iterative Tikhonov regularization method combined with a finite dimensional approximation to find a stable source term. Numerical examples are provided to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

CrO2 thin films epitaxially grown on the rutile TiO2 (001) substrate are studied via density function theory. Due to the strain from the substrate, a semiconductor to half-metal transition with the film growth is observed. It is found that, as the film is thicker than three atomic layers, the half-metallic property can be retained with an antiferromagnetic feature which reduces the total magnetic moment. With the help of ionic and the double exchange picture, the physics behind the half-metallic rebuilding process is revealed. [ABSTRACT FROM AUTHOR]

Inspired by recent progress of experimental fabrication of carbon structure [Borrnert et al., Phys. Rev. B 81, 085439 (2010)], we proposed a scheme to generate spin-polarized current based on an all-carbon system consisting of carbon nanotube and chain. The transmission spectra are calculated based on density functional theory combined with nonequilibrium Green's function method. It is found that the spin-polarized current can be achieved in the proposed system by partial contact between nanotube and chain, without using the dopants, ferromagnetic electrodes, and external electric field. Moreover, our results show that the device containing carbon nanotubes with large length and diameter can produce the current with 100% spin polarization, which is essential for spintronic devices. Physical mechanisms and the comparison with the results of graphene are also discussed. [ABSTRACT FROM AUTHOR]

The electronic and optical properties of codoped double-walled carbon nanotubes (DWNTs), in which nucleophilic atoms (potassium) are adsorbed outside the outer tube and electrophilic molecules (NO2) are adsorbed inside the inner tube, are investigated by density functional theory. It is found that the inner core tube is p-type doped and the outer shell tube is n-type doped, forming a radial p-n junction of DWNTs. A type-II band energy alignment is formed at the interface of two constituting walls of codoped DWNTs. Moreover, optical calculations show that the band edge absorption is zero for pristine DWNTs, while it is pronounced for the codoped DWNTs. This absorption of codoped DWNTs leads to charge separation in the interface of two walls of DWNTs with holes located on core tube while electrons located on shell one. The properties of DWNT coaxial nanocables demonstrated here can find future applications in electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Resistive switching memory cells with polycrystalline (AgI)0.2(Ag2MoO4)0.8 (AIMO) solid electrolyte films as storage medium were fabricated on SiO2/Pt/Ti/Si substrates by using pulse laser deposition technique and focused ion beam lithography. X-ray diffraction, scanning electron microscopy, and energy dispersive x-ray analysis have been employed to investigate the structure, the surface morphology, and the composition of AIMO thin films. The Ag/AIMO/Pt memory cells with sandwich structure exhibit stable, reproducible, and reliable resistive switching characteristics. The ratio of resistance between high resistance states and low resistance states can reach ∼105. Moreover, the low resistance is ∼500 Ω at a compliance current of 0.5 mA, which is favorable to reduce the power dissipation of the entire circuit. The switching-on mechanism has been discussed and the metallic conduction characteristic has also been verified. The fast response speed and the good retention properties further indicate that polycrystalline AIMO thin film is a potential candidate for the next generation nonvolatile memory. [ABSTRACT FROM AUTHOR]

Under the local-spin density approximation method plus on-site coulomb interaction U correction (LSDA+U), the BaCrO3 in the perovskite structure is found to be half-metallic ferromagnet with an integral magnet moment of 2.000 Bohr magnetons (μB) per unit. The feasibility of constructing the BaCr0.5Ti0.5O3 superlattice to stabilize the perovskite phase for the BaCrO3 is theoretically explored. Additionally, the influence of screened parameters U on the electronic structures and magnet moments of the perovskite BaCrO3 and BaCr0.5Ti0.5O3 superlattice is expounded. [ABSTRACT FROM AUTHOR]

1. A new assessment method for duck footpad dermatitis (FPD) evaluation was developed, combining visual and histological characters using the images and sections of 400 ducks' feet at 340 d of age. All ducks were graded as G0 (healthy), G1 (mild), G2 (moderate) and G3 (severe) according to the degree of FPD. 2. To reveal the potential biomarkers in serum related to duck FPD, non-targeted metabolomics and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were used to explore differential metabolites in each group. 3. There were 57, 91 and 210 annotated differential metabolites in groups G1, G2 and G3 compared with G0, which meant that the severity of FPD increased in line with the number of metabolites. Four metabolites, L-phenylalanine, L-arginine, L-leucine and L-lysine, were considered potential biomarkers related to FPD. 4. KEGG enrichment analysis showed that the FPD was mainly involved in glycolysis, the tricarboxylic acid (TCA) cycle, the pentose phosphate pathway and amino acid metabolism. These are related to production metabolism and can affect the physiological activities of ducks, which might explain the decrease in production performance. [ABSTRACT FROM AUTHOR]

The stability and structures of titanium-doped gold clusters AunTi (n=2–16) are studied by the relativistic all-electron density-functional calculations. The most stable structures for AunTi clusters with n=2–7 are found to be planar. A structural transition of AunTi clusters from two-dimensional to three-dimensional geometry occurs at n=8, while the AunTi (n=12–16) prefer a gold cage structure with Ti atom locating at the center. Binding energy and second-order energy differences indicate that the Au14Ti has a significantly higher stability than its neighbors. A high ionization potential, low electron affinity, and large energy gap being the typical characters of a magic cluster are found for the Au14Ti. For cluster-cluster interaction between magic transition-metal-doped gold clusters, calculations were performed for cluster dimers, in which the clusters have an icosahedral or nonicosahedral structure. It is concluded that both electronic shell effect and relative orientation of clusters are responsible for the cluster-cluster interaction. [ABSTRACT FROM AUTHOR]

We study the thermal conductivity of single-walled carbon nanotube bundles and multi-walled carbon nanotubes. It is shown that, for an individual single-walled carbon nanotube, its thermal conductivity is both diameter and chirality dependent. In defect-free bundles and multi-walled carbon nanotubes, the phonon essentially does not transcend the bonds between the constituent walls due to the weak intertube interaction. If, however, the intertube coupling is strong, a substantial reduction in the thermal conductivity maybe implied. Such a low thermal conductivity can be found in several thermal transport experiments of carbon nanotube mats. [ABSTRACT FROM AUTHOR]

Polarization shift and temperature sensitivity are important issues in optical waveguides. Applying stresses is a promising method to control these optical parameters. In this article, analytical solutions are obtained to estimate the stress effects on these optical parameters. Because the refractive index variation induced by the stresses is very small, the linear approximation is used to obtain the closed-form solutions to estimate the stress induced effective index change in a slab waveguide. The solutions are, then, extended to estimate the stress induced effective index change, polarization shift, and the temperature sensitivity of a channel waveguide by use of effective index method. As an example, the optical parameters controlled by the thermal stresses, which are induced by attaching an Al plate on the bottom of the substrate, are analyzed. The results show that the polarization shift and the temperature sensitivity of the central wavelength can be tuned in a large range by varying the Al plate thickness and the curing temperature. The effects can be modified by changing the shape of the Al plate. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the impact of the mitochondrial alternative oxidase (AOX) pathway on energy metabolism in chloroplasts, and evaluate the importance of the AOX in alleviating drought-induced photoinhibition in pepper (Capsicum annuum L.). Inhibition of AOX pathway decreased photosynthesis and increased thermal energy dissipation in plants under normal conditions. It indicated that AOX pathway could influence chloroplast energy metabolism. Drought reduced carbon assimilation. Photoinhibition was caused by excess of absorbed light energy in spite of the increase of thermal energy dissipation and cyclic electron flow around PSI (CEF-PSI). Upregulation of AOX pathway in leaves experiencing drought would play a critical role in protection against photoinhibition by optimization of carbon assimilation and PSII function, which would avoid over-reduction of photosynthetic electron transport chain. However, inhibition of AOX pathway could be compensated by increasing the thermal energy dissipation and CEF-PSI under drought stress, and the compensation of CEF-PSI was especially significant. [ABSTRACT FROM AUTHOR]

Abstract: The material point method (MPM) has attracted increasing attention from the graphics community, as it combines the strengths of both particle‐ and grid‐based solvers. Like the smoothed particle hydrodynamics (SPH) scheme, MPM uses particles to discretize the simulation domain and represent the fundamental unknowns. This makes it insensitive to geometric and topological changes, and readily parallelizable on a GPU. Like grid‐based solvers, MPM uses a background mesh for calculating spatial derivatives, providing more accurate and more stable results than a purely particle‐based scheme. MPM has been very successful in simulating both fluid flow and solid deformation, but less so in dealing with multiple fluids and solids, where the dynamic fluid‐solid interaction poses a major challenge. To address this shortcoming of MPM, we propose a new set of mathematical and computational schemes which enable efficient and robust fluid‐solid interaction within the MPM framework. These versatile schemes support simulation of both multiphase flow and fully‐coupled solid‐fluid systems. A series of examples is presented to demonstrate their capabilities and performance in the presence of various interacting fluids and solids, including multiphase flow, fluid‐solid interaction, and dissolution. [ABSTRACT FROM AUTHOR]

Based on density functional theory and nonequilibrium Green's function method, we study the magnetic order and collinear/noncollinear spin transport of 180 ∘ domain wall (DW) made by transition metal (TM)-doped Ni atomic chain. The results show that the TM doping reproduces characteristic features depending on the type of TM elements, the number of dopants and the initial magnetization distribution. In the collinear magnetization, which is obtained from the initial condition of abrupt DW, the two dopants show symmetric features while the single dopant presents a varying magnetic moment on the TM dopant when the number of 3d electrons of dopant increases. As the magnetization is noncollinear (spiral-like), the magnetization becomes complicated. For instance, the rotation sense of magnetization changes from clockwise to counter-clockwise for some TM dopants. In addition, the transmission of doped Ni chain shows two scattering mechanisms, i.e. electronic scattering due to quasi-bound state and due to the spin-flip scattering. Our results reported here provide considerable insights into the doping effect on magnetization and spin transport of atomic-scale DW. [ABSTRACT FROM AUTHOR]

Objective: The therapeutic potential of periodontal ligament cells for periodontal regeneration gradually decreases when cultured as a monolayer in vitro. Three‐dimensional cell culture models provide an alternative to traditional monolayer cell culture. This study aimed to comparatively evaluate the influence of spheroid culture on periodontal ligament cells. Materials and Methods: Chitosan films were used to culture three‐dimensional periodontal ligament cell spheroids. The proliferation, self‐renewal, and osteogenic capacity of periodontal ligament cells derived from spheroids were evaluated and compared with cells cultured on a monolayer. Results: Viable spheroids of periodontal ligament cells were formed on chitosan films. Compared to monolayer cell culture, periodontal ligament cells exhibited decreased proliferation upon spheroid formation. In contrast, their expression of genes related to self‐renewal was significantly higher comparison with cells cultured in a monolayer. Moreover, the formation of periodontal ligament cell spheroids increased their colony‐forming unit ability and osteogenic differentiation capacity. Conclusion: The results demonstrate the successful use of chitosan films for the culture of periodontal ligament cell spheroids. Compared to cells cultured in monolayer, periodontal ligament cells in spheroids did not proliferate, but exhibited higher self‐renewal gene expression, colony‐forming unit and osteogenic capacity. [ABSTRACT FROM AUTHOR]

The spin-dependent transport properties of Cu/EuO-based tunnel junctions are investigated by means of the first-principle calculations combined with the non-equilibrium Green's function (NEGF) method. It is found that the Cu/EuO-based junctions exhibit excellent spin-filtering effect. Furthermore, the mixed Cu/O layer enhances the tunneling of the majority spin through the EuO barrier for the junctions with Cu/O layers due to the fact that the valance-band maximum of the Eu-4 states shifts to high energies with respect to the Fermi level for these junctions. These results permit the existence of the mixed Cu/O layer in Cu/EuO-based tunnel junctions and promote future applications of these tunnel junctions in spintronic devices. [ABSTRACT FROM AUTHOR]

Thermoelectric materials are actively considered for waste heat recovery applications. To improve the thermoelectric (TE) performance, nanostructuring to reduce their thermal conductivity has been inferred as an effective approach. Here, we present our investigations of the influence of ball milling and hot pressing process parameters on the chemical and thermoelectric properties of the type-I clathrate Ba 8 Cu 4.5 Si 6 Ge 35.5 . Powders with very small grain sizes could be obtained by ball milling. However, in contrast to other materials, the ultra-fine powders deteriorate the sintering behavior in the hot pressing process. We suggest that this is mainly due to an oxygen-induced local decomposition of the clathrate phase, which might start from the surface of nanoparticles. Partial decomposition also occurs in sintered samples of low bulk density when they are heated under low vacuum conditions. Overall this leads to the loss of Si/Ge and thus to an enhanced Cu content in the remaining clathrate(s), which deteriorates the TE performance in spite of the reduced thermal conductivity. Thus, keeping the composition and structure of the clathrate stable during the nanostructuring process is essential for reaching high TE performance. [ABSTRACT FROM AUTHOR]

Mechanochemistry is emerging as a powerful solvent-free approach to chemical synthesis, having been applied to metal oxides, pharmaceutical materials, organic compounds and to a lesser extent, coordination complex synthesis. Notably, examples of applications of mechanochemical methodologies in the synthesis of main-group compounds are few and far between. Herein, we demonstrate that ball milling enabled the solvent-free synthesis of a range of phosphazane frameworks with a broad substrate scope, yielding seven new acyclic and macrocyclic species. The strength of this methodology is highlighted by a fast, selective and high-conversion product generation from poorly soluble starting materials, thereby demonstrating mechanochemistry as a real alternative to solution-based methods in synthetic main-group chemistry. [ABSTRACT FROM AUTHOR]

Motivated by a recent tunneling magnetoresistance (TMR) measurement in which the negative TMR is observed in MgO/NiO-based magnetic tunnel junctions (MTJs), we have performed systematic calculations of transmission, current, and TMR of Fe/MgO/NiO/Fe MTJ with different thicknesses of NiO and MgO layers based on noncollinear density functional theory and non-equilibrium Green's function theory. The calculations show that, as the thickness of NiO and MgO layers is small, the negative TMR can be obtained which is attributed to the spin mixing effect and interface state. However, in the thick MTJ, the spin-flipping scattering becomes weaker, and thus, the MTJs recover positive TMR. Based on our theoretical results, we believe that the interface state at Fe/NiO interface and the spin mixing effect induced by noncollinear interfacial magnetization will play important role in determining transmission and current of Fe/MgO/NiO/Fe MTJ. The results reported here will be important in understanding the electron tunneling in MTJ with the barrier made by transition metal oxide. [ABSTRACT FROM AUTHOR]

Objective: To explore HIFU treatment for uterine arteriovenous malformation.Design: A case report.Setting: Gynaecological department in a university teaching hospital of China.Population: A patient with uterine arteriovenous malformation.Methods: The diagnosis of uterine arteriovenous malformation was made through MRI. Ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation was performed.Main Outcomes Measures: HIFU is effective in treating uterine arteriovenous malformation.Results: The patient had reduction of the lesion volume and obvious symptom relief, without significant adverse effects.Conclusions: HIFU can be used as a new treatment option for uterine arteriovenous malformation.Tweetable Abstract: Ultrasound-guided high-intensity focused ultrasound ablation is effective in treating uterine arteriovenous malformation. [ABSTRACT FROM AUTHOR]

Complement activation has a deep pathogenic influence in immunoglobulin (Ig)A nephropathy (IgAN). C3a and C5a, small cleavage fragments generated by complement activation, are key mediators of inflammation. The fragments exert broad proinflammatory effects by binding to specific receptors (C3aR and C5aR, respectively). However, no studies thus far have investigated the effects of C3a, C5a and their receptors on IgAN. We observed that C3aR and C5aR antagonists repressed IgA-induced cell proliferation and interleukin (IL)-6 and monocyte chemotactic protein 1 (MCP-1) production in cultured human mesangial cells (HMCs). Furthermore, an IgAN mouse model induced by Sendai virus infection was employed to investigate the effects of C3aR and C5aR on IgAN in vivo for the first time. Wild-type (WT) and several knock-out mouse strains (C3aR-/- or C5aR-/-) were immunized intranasally with increasing doses of inactivated virus for 14 weeks and were subjected to two intravenous viral challenges during the time-period indicated. In the Sendai virus-induced IgAN model, C3aR/C5aR-deficient mice had significantly reduced proteinuria, lower renal IgA and C3 deposition, less histological damage and reduced mesangial proliferation compared with WT mice. Both C3aR deficiency and C5aR deficiency, especially C3aR deficiency, inhibited renal tumour necrosis factor (TNF)-α, transforming growth factor (TGF)-β, IL-1β, IL-6 and MCP-1 expression significantly. However, C3aR/C5aR-deficient and WT mice with IgAN did not differ with respect to their blood urea nitrogen (BUN) and serum creatinine levels. Our findings provide further support for the idea that C3aR and C5aR are crucially important in IgAN, and suggest that pharmaceutically targeting C3aR/C5aR may hold promise for the treatment of IgAN. [ABSTRACT FROM AUTHOR]

In terms of electric ship energy requirement in navigation, the ship charging station location is especially important. In this paper, a multi-period ship charging station location optimization model is proposed to make location decision in overall, from initial possible station sites chosen to the capacity determination for the final location sites. In the first phase, from the perspective of external environment, find out all possible ship charging station candidate sites through the feasible analyze. In the second phase, taking the ship charging demands into consideration, the final ship charging station sites can be selected among the candidate sites based on backup coverage model. In the last phase, regarding the cost of construction and service capability for different grade as the main factor in capacity determination, the optimal capacity of each final ship charging station are determined by means of optimization method. Finally, an example of Yanqi lake in China is used to verify the validity of the proposed methodology. The reasonable location of charging station could ensure the electric energy supply and avoid congestion caused by ship charging gathering. The model can be easily generalized to other problems regarding facility allocation based on user demand. [ABSTRACT FROM AUTHOR]

Objectives: Understanding the prevalence of cardiovascular disease (CVD) risk factors has an impact on the public policy for initiating CVD prevention. This study aimed to examine the prevalence of current smoking, overweight/obesity, hypertension, diabetes mellitus (DM), and dyslipidemia among Shenzhen residents and to investigate gender differences in CVD risk profiles to identify the subgroups at higher risk. Study design: A large cross-sectional study was conducted between April and May 2015. Results: The prevalence of current smoking, overweight/obesity, hypertension, DM, and dyslipidemia were 21.8%, 40.6%, 17.6%, 4.8%, and 35.7%, respectively. Clustering of two or more or three or more of CVD risk factors was noted in 35.7% and 14.1% of participants. The prevalence of current smoking (45.0% vs 1.1%, P < 0.001), overweight/obesity (48.5% vs 33.4%, P < 0.001), hypertension (19.7% vs 15.7%, P < 0.05), and dyslipidemia (46.5% vs 20.5%, P < 0.001) was found higher among male than among female participants. Conclusions: This study adds to the evidence suggesting high prevalence rates of CVD risk factors and composite measures among Shenzhen residents. The higher level of CVD risk factors in male than in female residents is suggested. Effective population-based intervention programs such as smoking cessation, early detection, management, and treatment of hypertension, DM, and dyslipidemia should be initiated and enhanced especially among the males. [ABSTRACT FROM AUTHOR]

There is a significant potential for nuclear combined heat and power (CHP) in quite a number of industries. The reactor concepts of the next generation would be capable to open up, in particular, the high temperature heat market where nuclear energy is applicable to the production processes of hydrogen (or liquid fuels) by steam reforming or water splitting. Due to the need to locate a nuclear facility near the hydrogen plant, an overall safety concept has to deal with the question of safety of the combined nuclear/industrial system by taking into account a qualitatively new class of events characterized by interacting influences. Specific requirements will be determined by such factors as the reactor type, the nature of the industrial process, the separation distances of the industrial facility and population centers from the nuclear plant, and prevailing public attitudes. Based on the Japanese concept of the GTHTR300C nuclear reactor for electricity and hydrogen cogeneration, theoretical studies were conducted on the release, dispersive transport, and explosion of a hydrogen cloud in the atmosphere for the sake of assessing the required minimum separation distance to avoid any risk to the nuclear plant's safety systems. In the case of sulfur-iodine water splitting, the accidental release of process intermediates including large amounts of sulfur dioxide, sulfur trioxide, and sulfuric acid need to be investigated as well to estimate the potential risk to nuclear installations like the operators' room and estimate appropriate separation distances against toxic gas propagation. Results of respective simulation studies will be presented. [ABSTRACT FROM AUTHOR]

A multi-ship collision avoidance decision-making and path planning formulation is studied in a distributed way. This paper proposes a complete set of solutions for multi-ship collision avoidance in intelligent navigation, by using a top-to-bottom organization to structure the system. The system is designed with two layers: the collision avoidance decision-making and the path planning. Under the general requirements of the International Regulations for Preventing Collisions at Sea (COLREGs), the performance of distributed path planning decision-making for anti-collision is analyzed for both give-way and stand-on ships situations, including the emergency actions taken by the stand-on ship in case of the give-way ship's fault of collision avoidance measures. The Artificial Potential Field method(APF) is used for the path planning in details. The developed APF method combined with the model of ship domain takes the target ships' speed and course in-to account, so that it can judge the moving characteristics of obstacles more accurately. Simulation results indicate that the system proposed can work effectiveness. [ABSTRACT FROM AUTHOR]

The NaYF Yb, Re@NaYF@SiO (RE = Er, Tm) core-shell-shell nanophosphors were synthesized by thermal decomposition of lanthanide trifluoroacetate precursors and subsequent hydrolysis coating process. Structures of resulting nanophosphors are studied by the X-ray diffraction and high-resolution transmission electron microscopy. Temperature-dependent photoluminescence spectra, thermal quenching ratios, fluorescence intensity ratios, and temperature sensitivity of resulting nanoparticles are studied in the temperature range from 298 to 623 K. The results suggest that the NaYF:Yb, Er@NaYF@SiO is a suitable candidate for making a low temperature sensor up to 450 K with a maximum sensitivity of 24 × 10 K, and the NaYF:Yb, Tm@NaYF@SiO is an excellent candidate for temperature sensors at high temperature. This work presents a new method to use the fluoride nanocrystals as the optical thermometry at high temperature. [ABSTRACT FROM AUTHOR]

All reported attempts to synthesize the tert-butyl-substituted adamantoid phosph(III)azane P4(N tBu)6 have failed, leading to the classification of this molecule as inaccessible and a literature example of steric control in chemistry of phosphorus-nitrogen compounds. We now demonstrate that this structure is readily accessible by a solvent-free mechanochemical milling approach, highlighting the importance of mechanochemical reaction environments in evaluating chemical reactivity. [ABSTRACT FROM AUTHOR]

All reported attempts to synthesize the tert-butyl-substituted adamantoid phosph(III)azane P4(N tBu)6 have failed, leading to the classification of this molecule as inaccessible and a literature example of steric control in chemistry of phosphorus-nitrogen compounds. We now demonstrate that this structure is readily accessible by a solvent-free mechanochemical milling approach, highlighting the importance of mechanochemical reaction environments in evaluating chemical reactivity. [ABSTRACT FROM AUTHOR]

Thermal expansion, electrical conductivity, hardness and friction property of Mn3ZnN, which had been doped with Sn, Ag or Ni and sintered at 1223 K, were measured. X-ray diffraction analyses show that these compounds have a cubic antiperovskite Mn3CuN-type structure and negative thermal expansion (NTE). The width of NTE operation temperature (ΔT) and the coefficient of thermal expansion are different when Mn3ZnN was doped with different element. A giant NTE coefficient of −81.00 × 10−6 K−1is obtained from Mn3Zn0.5Ag0.5N while ΔTis 18 K. A broad ΔTof 60 K is obtained from Mn3Zn0.5Sn0.5N with thermal expansion coefficient of −19.05 × 10−6 K−1. The results show that Mn3Zn0.5A0.5N (A = Sn, Ag, Ni) has good electrical conductivity. The electrical conductivity of Mn3Zn0.5Ag0.5N is the largest among these compounds as 2.45 × 103 S cm−1. The Vickers hardness of these compounds is more than 350 HV. The friction coefficients of Mn3Zn0.5Ag0.5N, Mn3Zn0.5Ni0.5N and Mn3Zn0.5Sn0.5N are 0.5318, 0.4554 and 0.2336, respectively. [ABSTRACT FROM AUTHOR]

We employ a facile approach to fabricate the novel graphene/Fe 3 O 4 /carbon microtube-nanocomposite with the hierarchical sandwich-type architecture by the addition of the trace amount of the carbon microtubes. This new microstructure effectively avoids the agglomeration of graphene and keeps the characteristic of stronger and broader absorption with lighter density. Results indicate that the graphene/Fe 3 O 4 /carbon microtube-nanocomposite with the sandwich-type architecture has a strong RL (about − 50 dB) at a band of about 4 GHz, highlighting its importance for microwave absorbing applications. [ABSTRACT FROM AUTHOR]