Search

The Brown–Preston–Singleton (BPS) stopping power model is added to our previously developed hybrid code to model ion beam–plasma interaction. Hybrid simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target, in which they compete with each other. When the target is not completely ionized, the self-generated resistive field effect dominates over the ion scattering effect. However, when the target is completely ionized, this situation is reversed. Moreover, it is found that Ohmic heating is important for higher current densities and materials with high resistivity. The energy fraction deposited as Ohmic heating can be as high as 20%–30%. Typical ion divergences with half-angles of about 5°–10° will modify the proton energy deposition substantially and should be taken into account. [ABSTRACT FROM AUTHOR]

Ultra-intense laser-driven fast electron beam propagation in a silicon target is studied by three-dimensional hybrid particle-in-cell–fluid simulations. It is found that the transverse spatial profile of the fast electron beam has a significant influence on the propagation of the fast electrons. In the case of a steep spatial profile (e.g., a super-Gaussian profile), a tight fast electron beam is produced, and this excites more intense resistive magnetic fields, which pinch the electron beam strongly, leading to strong filamentation of the beam. By contrast, as the gradient of the spatial profile becomes more gentle (e.g., in the case of a Lorentzian profile), the resistive magnetic field and filamentation become weaker. This indicates that fast electron propagation in a solid target can be controlled by modulating the spatial gradient of the laser pulse edge. [ABSTRACT FROM AUTHOR]

Neutron detection technology is a powerful method for characterizing fundamental and industrial materials, such as magnetic materials, nanomaterials, polymers, and biological substances. A compact pulsed neutron source is desired, as the traditional way of producing high-yield neutrons depends mainly on large-scale accelerators or fission reactors. Here, we propose a scheme to generate a high-yield pulsed neutron source by using a > 100 fs relativistic laser pulse interacting with a micro-structure assisted pitcherâ€"catcher target. Three-dimensional particle-in-cell and Monte Carlo hybrid simulations demonstrate that an energetic deuterium ion beam with a cutoff energy of 75 MeV and a 7.23 % laser-to-deuterium energy conversion efficiency can be obtained with a laser pulse of intensity 1.37 Ă— 10 20 W cmâˆ'2, duration 330 fs, power 34 TW and energy 6.7 J. When they strike the following lithium fluoride converter of thickness 2 cm, a large number of neutrons are thus produced via a 7Li(d,n) nuclear reaction. The neutron yield is up to 109 and its pulse duration is as short as 20 ps. This scheme could be realized in laboratories with current hundreds-of-terawatt or multi-petawatt laser facilities. [ABSTRACT FROM AUTHOR]

This paper uses the Split Hopkinson Pressure Bar (SHPB) test to analyze the aluminum honeycomb's dynamic and failure behavior under different strain rates. At the same time, we propose a modeling method. The representative volume element (RVE) models the complex materials. On this basis, the equivalent material parameters of complex materials are calculated. Taking the aluminum honeycomb material as an example, we use the equivalent material parameters calculated by the representative volume element of aluminum honeycomb to construct the macro-model of the aluminum honeycomb and compare it with the refined model of aluminum honeycomb. According to the SHPB test of aluminum honeycomb, the finite element models are compared and calibrated, and the accuracy of the finite element model is verified. It is expected to provide a reference for applying aluminum honeycomb materials in various fields, the dynamic behavior of aluminum honeycomb, and the combined use of multi-scale finite element modeling. [ABSTRACT FROM AUTHOR]

The generation and stopping of a laser-driven two-component ion beam are investigated by three-dimensional particle-in-cell simulation and an extended stopping model. It is found that a two-component ion beam with the tunable composition ratio can be obtained from the two-species-ions sandwich target interacting with a relativistic laser pulse. When the generated proton beam mixed with a certain portion of carbon ions is transporting in fully ionized dense plasma, the beam stopping power is significantly enhanced compared to a pure proton beam. The maximum penetration depth is sharply reduced, and the Bragg peak with a higher magnitude appears earlier at the end of their paths, which is beneficial for achieving more localized energy deposition. The effect of heavy ion mixing on proton beam driven fast ignition is also discussed. A simple theoretical model is established, indicating that the required ignition time is relatively delayed for a heavy-ion doping case. For a small hot-spot size, it is possible to achieve the fusion ignition for a low mixed ratio. However, it is difficult to maintain a high fuel temperature due to the growing energy loss originating from mechanical work and thermal conduction. [ABSTRACT FROM AUTHOR]

By using two-dimensional particle-in-cell simulations, we propose a scheme for strong coupling of a petawatt laser with an opening gold cone filled with near-critical-density plasmas. When relevant parameters are properly chosen, most laser energy can be fully deposited inside the cone with only 10% leaving the tip opening. Due to the asymmetric ponderomotive acceleration by the strongly decayed laser pulse, high-energy-density electrons with net laser energy gain are accumulated inside the cone, which then stream out of the tip opening continuously, like a jet. The jet electrons are fully relativistic, with speeds around 0.98 - 0.998 c and densities at 1020/cm3 level. The jet can keep for a long time over 200 fs, which may have diverse applications in practice. [ABSTRACT FROM AUTHOR]

Collision of intermediate-energy heavy ions is an important way to investigate the state of high-density nuclear matter and formation of quark gluon plasmas. In this paper, we demonstrate from two-dimensional particle-in-cell simulations that hundreds-GeV Au79+ ions can be generated by ultrashort ∼1022–24 W cm−2 lasers interacting with high-Z grain doped gas. Under extremely intense laser field, strong γ-ray radiation has resulted in massive laser energy loss, and the invoked radiation reaction trapping of electrons weakens the heavy ion acceleration. However, due to hole-boring acceleration and multi-body expansion acceleration of high-Z grains, the energy conversion efficiency from laser to heavy ions is still up to 32%. Our results might provide an effective routine to carry out the experimental explorations of heavy-ion collisions by using hundreds-petawatt laser facilities. [ABSTRACT FROM AUTHOR]

1. Duck meat is considered a delicacy, but choosing the best meat is problematic. Caveolin-3 (CAV-3) is a muscle-specific protein marker in animals. The goal of the current study was to detect the characteristics of CAV-3 gene in ducks. 2. Full-length CAV-3 was acquired from ducks (Anas platyrhynchos) using reverse transcriptase PCR and rapid amplification of cDNA ends. DNAMAN software was used for homology comparisons. Quantitative reverse transcription-PCR, PCR-single-strand conformation polymorphism, and sequencing were used to determine CAV-3 expression and polymorphism of a single nucleotide, respectively. The study examined four types of ducks, including Jinding, Chaohu, Cherry Valley, and Gaoyou ducks. 3. The study acquired 1066 bp of CAV-3 cDNA sequences, including a 456 bp complete open reading frame encoding 151 amino acids. Both coding sequences (CDSs) and translated amino acids exhibited highest homology with Gallus gallus (CDS homology 91.67%, amino acids 94.04%), followed by mammalian species (CDS homology 79.0%, amino acids 78.0%). Single nucleotide polymorphism analysis revealed five mutations in exons (A489G, G501A, A557G, T563A, and A602G), and a C805T mutation in an intron. Among amplified polymorphic loci detected using primer 2, allele frequency was higher for A (489A501G507A563T602A) than B (489G501G507G563T602C) or C (489G501A507G563A602C). The highest occurred in Cherry Valley ducks (0.7587). Using primer 4, the M allele frequency was higher than that of the N allele. CAV-3 was most highly expressed in the heart, followed by skeletal muscles. Additionally, CAV-3 had higher expression in heart and breast muscle of overfed Muscovy ducks than control ducks, but no difference was seen in thigh muscle. 4. CAV-3 in ducks had the highest homology with Gallus gallus CAV-3, and it could be used as a marker for muscle quality in ducks. [ABSTRACT FROM AUTHOR]

Apatinib (YN968D1) is a novel and highly selective tyrosine kinase inhibitor that inhibits vascular endothelial growth factor receptor-2 (VEGFR-2) and is approved as a third-line and subsequent-line treatment for advanced gastric adenocarcinoma or gastroesophageal junction adenocarcinoma in China. Apatinib is also widely studied in other solid tumors. With the increase in clinical research of apatinib, its adverse effects have also received widespread attention. Hence, this article summarizes the pharmacological properties of apatinib and reviews its clinical use in advanced or metastatic cancers. We highlight the common adverse reactions of apatinib in clinical applications and we also clarify the corresponding prevention and intervention measures. Overall, this review will help us better understand the safety and efficacy of apatinib treatment. [ABSTRACT FROM AUTHOR]

By using three-dimensional particle-in-cell simulations, we demonstrate that an energetic ring-shaped ion beam can be generated by an ultra-intense circularly polarized Laguerre–Gaussian laser pulse interacting with micro-structure targets. The electron and ion dynamics of three different targets including a sleeve–wire target, wire target, and common planar target are investigated. It is found that an optimized sleeve–wire target can provide a remarkable increase in the maximum ion energy and laser-to-ion energy conversion efficiency. The reason can be attributed to the matched transverse profiles between the electric-field distribution of Laguerre–Gaussian laser and sleeve–wire structure, resulting in efficient laser-target energy coupling. In fact, using a laser pulse of intensity 2.74 × 1 0 20 W/cm2, duration 66.7 fs, and energy ∼1 J, one can obtain ∼35 MeV protons, ∼5.8 MeV/u carbon ions, and ∼15% laser-to-ion energy conversion. [ABSTRACT FROM AUTHOR]

Target-normal sheath acceleration (TNSA) of ions by >100-fs relativistic laser pulses irradiating a multichannel target consisting of a row of parallel long wires and a plane back foil is studied. Two-dimensional particle-in-cell simulations show that the laser light pulls out from the wires a large number of dense hot attosecond electron bunches, which are synergetically accelerated forward by the relativistic ponderomotive force of the laser as well as the longitudinal electric field of a transverse magnetic mode that is excited in the vacuum channels between the wires. These electrons are characterized by a distinct two-temperature energy spectrum, with the temperature of the more energetic electrons close to twice the ponderomotive potential energy. After penetrating through the foil, they induce behind its rear surface a sheath electric field that is both stronger and frontally more extended than that without the channels. As a result, the TNSA ions have much higher maximum energy and the laser-to-ion energy conversion efficiency is also much higher. It is found that a laser of intensity 1.37 × 1020 W/cm2, duration 165 fs, and energy 25.6 J can produce 85 MeV protons and 31 MeV/u carbon ions, at 30% laser-to-ion energy conversion efficiency. The effects of the channel size and laser polarization on the TNSA ions are also investigated. [ABSTRACT FROM AUTHOR]

Multi‐phase DC/DC converter is widely used in fuel cell vehicles to adjust the voltage. Single phase mode of converter is adopted to increase efficiency when current ripple meets requirement. Therefore, it is necessary to commutate between different phases at low frequency, due to the temperature rising of each phase‐leg. However, narrow pulse current occurs during the phase commutation. Pulse current can cause variations in water and gas content inside the proton exchange membrane fuel cell (PEMFC), which is the driving force for degradation. To analyze the effect of low frequency narrow pulse current on fuel cell, an isothermal 1D‐PEM fuel cell model is presented to characterize the transient changes of these parameters: gas stoichiometry, relative humidity, water content and pressure difference. After comparing the influence on fuel cell of four types of pulse current, the results reveal that the 4 ms narrow pulse current cannot affect fuel cell lifetime, since no gas shortage occurred, the change of relative humidity and membrane water content are less than 1‰ and the pressure difference varies within specified range. Besides, the membrane lifetime reduces to 4,166 h as the width of narrow pulse current increased from 4 ms to 0.8 s. [ABSTRACT FROM AUTHOR]

An all-optical method for generating ultra-intense high-order-mode light pulse is investigated with three-dimensional particle-in-cell simulation. We find that the conversion from a short intense circularly polarized incident Gaussian laser pulse into a transverse magnetic (TM) mode occurs as it propagates into a micro plasma waveguide. The strength of the longitudinal electric field of the excited TM modes can be almost two orders of magnitude higher than that of the original laser. The simulation results show that, for the lower-order modes, the trapped electrons lead to their revolving transverse structures. A linear plasma waveguide model is presented to predict the mode pattern and intensity of the longitudinal electric fields, which are in excellent agreement with those in the simulations. Relativistic-intense high-order-mode light can be useful for many applications, including accelerating charged particles to high energies. [ABSTRACT FROM AUTHOR]

With the growth of population and the rapid development of economic level, the emission of greenhouse gases increases greatly, and the form, degree and structure of resource utilization tend to be diversified. Based on the diversity of ecological environment, the utilization of resources shows the diversity of utilization functions. However, the unreasonable carbon emission leads to the decrease of the resource carrying capacity, and its prominent impact on the ecological environment is reflected in the population growth, the inharmonious development of the energy consumption and the urban greening construction. The results of this study show that economic development and forest city construction mutually promote each other. Expanding forest area and improving urban forest accessibility are the most direct effective way to achieve direct emission reduction and forest city target requirements. Based on the four major categories including basis, ecology, economy and industry, and culture covering 12 small indicators proposed by SWOT analysis, technical supports should be provided to the specific forest city planning and construction. This study provides a theoretical basis for the sustainable development of lowcarbon environment. [ABSTRACT FROM AUTHOR]

1. Limiting the growth of adipose tissue in chickens is a major issue in the poultry industry. In chickens, de novo synthesis of lipids occurs primarily in the liver. Thus, it is necessary to understand how fatty acid accumulation in the liver is controlled. The miR-33 is an intronic microRNA (miRNA) of the chicken sterol regulatory element binding transcription factor 2 (SREBF2), which is a master switch in activating many genes involved in the uptake and synthesis of cholesterol, triglycerides, fatty acids and phospholipids. 2. In the current study, the genes CROT and HADHB known to encode enzymes critical for fatty acid oxidation were predicted to be potential targets of miR-33 in chickens via the miRNA target prediction programs 'miRanda' and 'TargetScan'. Co-transfection and dual-luciferase reporter assays showed that the expression of luciferase reporter gene linked to the 3ʹ-untranslated region (3ʹUTR) of the chicken CROT and HADHB mRNA was down-regulated by overexpression of the chicken miR-33 (P < 0.05). This down-regulation was completely abolished when the predicted miR-33 target sites in the CROT and HADHB 3ʹUTR were mutated. 3. Transfecting miR-33 mimics into the LMH cells led to a decrease in the mRNA expression of CROT and HADHB (P < 0.01), and this transfection had a similar effect on the proteins (P < 0.05). In contrast, the expression of CROT in primary chicken hepatocytes was up-regulated after transfection with the miR-33 inhibitor LNA-anti-miR-33 (P < 0.05). 4. Using quantitative RT-PCR, it was shown that the expression of miR-33 was increased in the chicken liver from day 0 to day 49 of age, whereas the CROT and HADHB mRNA levels decreased during the same period. 5. These findings support the conclusion that miR-33 might play an important role in lipid metabolism in the chicken liver by negatively regulating the expression of the CROT and HADHB genes, which encode enzymes critical for lipid oxidation. [ABSTRACT FROM AUTHOR]

Superlattices (SLs) consisting of multiferroic BiFeO3 (BFO) and dielectric Ba0.7Sr0.3TiO3 were epitaxially grown on a (001)-oriented Nb:SrTiO3 substrate using pulsed laser deposition. An improved ferroelectricity with a high-temperature polarization of ∼63.7 μC/cm2 at 470 K was observed. The SL exhibited both dielectric and magnetic relaxation properties. Two distinct dielectric relaxations were found: a carrier hopping process between Fe2+ and Fe3+ from 273 to 410 K and the long-range migration of oxygen vacancies from 430 to 573 K. Spin-glass behavior with a freezing temperature of ∼86.6 K was also observed. This work provides a promising path forward to tailor the multiferroic properties of BFO-based structures for high-temperature applications. [ABSTRACT FROM AUTHOR]

Mechanisms of fast electron energy deposition in dense magnetized plasma are studied by hybrid particle-in-cell/fluid simulations. It is found that the energy deposition ratio of Ohmic heating and collisional heating can be enhanced significantly as an Al target is presented in a strongly axial magnetic field, attributed to the fast electrons rotating around the axial field. The weight of Ohmic heating is increased with laser intensity during ultraintense laser-driven fast electrons propagating both in magnetized and unmagnetized solid targets, which is the dominant heating mechanism as the laser intensity is greater than 1018 W/cm2 compared to the collisional heating. The degree of the axial magnetic field effect on the fast electron energy deposition mechanisms is dependent on target materials, which is much weaker for low-Z targets, such as CH2. The results here should be helpful for the target designing of fast electron applications. [ABSTRACT FROM AUTHOR]

Nonlinear behaviors of stimulated Raman scattering driven by finite bandwidth pumps are studied by one dimensional particle-in-cell simulations. The broad spectral feature of plasma waves and backscattered light reveals the different coupling and growth mechanisms, which lead to the suppression effect before the deep nonlinear stage. It causes nonperiodic plasma wave packets and reduces packet and etching velocities. Based on the negative frequency shift and electron energy distribution, the long-time evolution of instability can be divided into two stages by the relaxation time. It is a critical time after which the alleviation effects of nonlinear frequency shift and hot electrons are replaced by enhancement. Thus, the broadband pump suppresses instability at early time. However, it aggravates in the deep nonlinear stage by lifting the saturation level due to the coupling of the incident pump with each frequency shifted plasma wave. Our simulation results show that the nonlinear effects are valid in a bandwidth range from 2.25% to 3.0%, and the physics are similar within a nearby parameter space. [ABSTRACT FROM AUTHOR]

Objectives: Biological age (BA) has been proposed to evaluate the aging status in an objective way instead of chronological age (CA). The purpose of our study is to construct a more precise formula of BA in the cross-sectional study based on a largest-ever sample of our studies. This formula aims at better evaluation of body function and exploring the disciplines of aging in different genders and age stages. Methods: A total of 1,373 healthy Chinese Han (age range, 19-93 years) were recruited from five cities in China, including 581 males and 792 females. Physical examination, blood routine, blood chemistry, and other lab tests were performed to obtain a total of 74 clinical variables. Then, the principal component analysis (PCA) was used to select variables and estimate BA. The BA formula was further validated in a population with some diseases (n=266), including cardiovascular diseases, type 2 diabetes, kidney diseases, pulmonary diseases, cancer and disorders in nervous system. Results: The BA formula was constructed as follows: BA = 0.358 (pulse pressure) + 0.258 (trail making test)-11.552 (mitral valve E/A peak) + 26.383 (minimum intima-media thickness) + 31.965 (Cystatin C) + 0.163 (CA)-3.902. In validation of the formula, BAs of patients were older than those of healthy persons. The BA accelerates faster in the middle-aged population than in the elderly population (>75 years old). Conclusion: This BA formula can reflect health condition changes of aging better than CA in a Chinese Han population. [ABSTRACT FROM AUTHOR]

Leptin levels are increased in patients with systemic lupus erythematosus (SLE) but little is known on how this correlates with several disease characteristics including the frequency of regulatory T cells (Tregs). Here we compared serum leptin levels with frequency of circulating Tregs in 47 lupus patients vs. 25 healthy matched controls. Correlations with lupus disease activity were also analyzed, as well as Treg proliferation potential. It was found that leptin was remarkably increased in SLE patients as compared to controls, particularly in SLE patients with moderate and severe active SLE, and the increase correlated with disease activity. Importantly, increased leptin in lupus patients inversely correlated with the frequency of Tregs but not in controls, and leptin neutralization resulted in the expansion of Tregs ex vivo. Thus, hyperleptinemia in lupus patients correlates directly with disease activity and inversely with Treg frequency. The finding that leptin inhibition expands Tregs in SLE suggests possible inhibition of this molecule for an enhanced Treg function in the disease. [ABSTRACT FROM AUTHOR]

High-quality lead-free BiNaTiO (BNT)/LaSrMnO (LSMO) bilayer was grown on SrTiO crystal by pulsed laser deposition method. Ferroelectric and electrical properties of the Pt/BNT/LSMO heterostructure have been investigated. Interestingly, an asymmetric current-voltage hysteresis exhibits a ferroelectric BNT modulated resistive switching characteristics in BNT/LSMO heterostructure without a forming process. The On/Off ratio of resistance switching behaviors is higher than 10 and retention time is longer than 10 s. The relationship between potential barriers and polarization charges at the Pt/BNT and BNI/LSMO interfaces has been discussed. The Pt/BNT/LSMO cell with both high On/Off ratio and long retention properties exhibits potentials in lead-free nonvolatile memory applications. [ABSTRACT FROM AUTHOR]

NAC is one of the most abundant plant-specific groups of transcription factors, which play important roles in plant growth and development regulation, as well as in biotic and abiotic stress responses. In the present study, a stress-responsive NAC gene, AhNAC4, was isolated from a cDNA library of peanut ( Arachis hypogaea L.) immature seeds, and characterized for its role in drought tolerance. AhNAC4 shared high amino acid similarity with NAC proteins belonging to the ATAF subfamily. The expression analysis indicated that AhNAC4 was highly induced by drought, salinity and ABA treatments. Transient expression analysis showed the AhNAC4-GFP fusion protein was exclusively localized in the nucleus of onion epidermal cells. Transactivation assays in yeast cells demonstrated that AhNAC4 functioned as a transcription activator and its C-terminus contained the activation domain. Overexpression of AhNAC4 confers enhanced drought tolerance in transgenic tobacco plants. The improved drought tolerance was associated with more stomatal closure and higher water use efficiency. Collectively, our results indicated that AhNAC4 functions as an important regulator in response to drought stress. [ABSTRACT FROM AUTHOR]

Objective The bacterial community structure of buccal mucosa in patients with oral lichen planus was evaluated and compared with healthy control. Subjects and Methods Buccal scraping samples have been taken on 43 oral lichen planus patients (21 erosive and 22 non-erosive) and 21 mucosal healthy volunteers. The V3 hypervariable 16S rDNA region was amplified and sequenced by high-throughput 454 pyrosequencing. Results 94.26% of the total buccal bacteria were classified into 15 abundant genera. Eight of these abundant genera could be detected in all cases, namely Streptococcus, Prevotella, Haemophilu, Neisseria, Fusobacterium, Leptotrichia, Veillonella and Actinomyces. Four abundant bacteria showed significantly different prevalence at the genus level: Streptococcus was more abundant ( P < 0.01) in healthy control group, while Fusobacterium ( P < 0.01), Leptotrichia ( P < 0.001) and Lautropia ( P < 0.001) showed higher abundance in OLP group. Few differences can be found between erosive and non-erosive OLP. In general, 19 'core' OTUs at three levels were defined to be OLP specific, comparing with healthy control group. Conclusions These results suggest that OLP is associated with dysbiosis of the oral microbiome. Further studies should be taken to elucidate the inner relationship between these observed changes and OLP development. [ABSTRACT FROM AUTHOR]

A mechanism of the acceleration and focusing of quasi-monoenergetic proton beams from a thin arched carbon-hydrogen target irradiated by a relativistic-intensity laser pulse is investigated by multi-dimensional particle-in-cell (PIC) simulations. As an intense linearly polarized laser pulse impinges on the thin target, a considerable number of electrons are evacuated, leading to Coulomb explosion in the excess positive charges left behind. Accompanying with the acceleration, the protons are focused ballistically in the Coulomb field, which is mainly contributed by the carbon ions. It is demonstrated that a quasi-monoenergetic proton bunch with the energy-density as high as 1017 J/m3 is produced by using a laser pulse with the intensity of 1021W/cm2. An analytical model is proposed to predict the proton energy and the focal position, which is fairly consistent with PIC simulations. [ABSTRACT FROM AUTHOR]

In this paper, the failure behavior of plasma-sprayed yttria-stabilized zirconia thermal barrier coatings fabricated by atmospheric plasma spraying (APS-TBCs) under three-point bending (3PB) test has been characterized via acoustic emission (AE) technique. Linear positioning method has been adopted to monitor dynamic failure process of the APS-TBCs under 3PB test. The investigation results indicate that the variation of AE parameters (AE event counts, amplitudes and AE energy) corresponds well with the change of stress-strain curve of the loading processes. The failure mechanism was analyzed based on the characteristics of AE parameters. The distribution of frequency of crack propagation has been obtained. The AE signals came from two aspects: i.e., plastic deformation of substrates, initiation and propagation of the cracks in the coatings. The AE analysis combined with cross-sectional observation has indicated that many critical cracks initiate at the surface of the top-coat. And some main cracks tend to propagate toward the substrate/bond-coat interface. The actual failure mechanism of the APS-TBCs under 3PB test is attributed to the debonding of metallic coating from the substrates and the propagation of the horizontal crack along the substrate/bond-coat interface under the action of flexural moment. [ABSTRACT FROM AUTHOR]

Image reconstruction in electrical capacitance tomography is an ill-posed inverse problem, and regularization techniques are usually used to solve the problem for suppressing noise. An anisotropic regional regularization algorithm for electrical capacitance tomography is constructed using a novel approach called spectral transformation. Its function is derived and applied to the weighted gradient magnitude of the sensitivity of Laplacian as a regularization term. With the optimum regional regularizer, the a priori knowledge on the local nonlinearity degree of the forward map is incorporated into the proposed online reconstruction algorithm. Simulation experimentations were performed to verify the capability of the new regularization algorithm to reconstruct a superior quality image over two conventional Tikhonov regularization approaches. The advantage of the new algorithm for improving performance and reducing shape distortion is demonstrated with the experimental data. [ABSTRACT FROM AUTHOR]

Generation of relativistic electron (RE) beams during ultraintense laser pulse interaction with plasma targets is studied by collisional particle-in-cell simulations. A strong magnetic field with a transverse scale length of several local plasma skin depths, associated with RE current propagation in the target, is generated by filamentation instability in collisional plasmas, inducing a great enhancement of the divergence of REs compared to that of collisionless cases. Such an effect is increased with laser intensity and target charge state, suggesting that the RE divergence might be improved by using low-Z materials under appropriate laser intensities in future fast ignition experiments and in other applications of laser-driven electron beams. [ABSTRACT FROM AUTHOR]

A ferroelectric/multiferroic structure composed of (PbSr)TiO (PST) and (BiLa)FeO (BLF) was heteroepitaxially deposited on a LaNiO buffered (001) SrTiO substrate by pulse laser deposition. Interestingly, the PST layer was acting as a buffering layer between BLF and electrode to suppress the migration of free carries in the heterostructure. A well-grown crystalline dense structure was observed from the surface morphology of PST/BLF/PST heterostructure. Moreover, the PST/BLF/PST trilayer exhibited improved ferroelectric and dielectric behaviors, together with two orders of magnitude lower leakage current and higher dielectric constant. Our result indicate that the multiferroic PST/BLF/PST heterostructure may have a promising application for the future high-density memory. [ABSTRACT FROM AUTHOR]

Silicon on insulator (SOI)-based transistors gated by nanogranular SiO2 proton conducting electrolytes were fabricated to mimic synapse behaviors. This SOI-based device has both top proton gate and bottom buried oxide gate. Electrical transfer properties of top proton gate show hysteresis curves different from those of bottom gate, and therefore, excitatory post-synaptic current and paired pulse facilitation (PPF) behavior of biological synapses are mimicked. Moreover, we noticed that PPF index can be effectively tuned by the spike interval applied on the top proton gate. Synaptic behaviors and functions, like short-term memory, and its properties are also experimentally demonstrated in our device. Such SOI-based electronic synapses are promising for building neuromorphic systems. [ABSTRACT FROM AUTHOR]

The preconditioned density-based algorithm and two-domain approach were used to investigate the fluid flow and heat transfer characteristics in a channel with staggered porous/solid ribs. In the porous zone, the momentum equations were formulated by the Darcy–Brinkman–Forchheimer model; and the local thermal equilibrium (LTE) model was adopted for energy equation. At the porous/fluid interface, the stress–continuity interfacial condition was utilized. The governing equations are solved by the preconditioned density-based control-volume method, with preconditioning matrix for equations of porous domain adopted, aiming to eliminate the equation stiffness of the porous seepage flow. The effects of Reynolds number, geometry parameters of ribs (rib length and thickness), and physical property of porous media (permeability and porosity) on the flow pattern and heat transfer performance were analyzed. Results indicate that, compared with that of solid ribs, the recirculating bubble behind the porous ribs is completely detached from it because of the permeability of porous media, and the size of the recirculating bubble is suppressed. The parameters that would affect the mass flow of fluid penetrating the porous ribs, including permeability, Reynolds number, baffle length and thickness, have remarkable influence on the flow pattern. All the aforementioned parameters would affect the local heat transfer performance. [ABSTRACT FROM AUTHOR]

It is demonstrated through particle-in-cell simulations that target-normal-sheath-accelerated protons can be well controlled by using a guiding cone. Compared to a conventional planar target, both the collimation and number density of proton beams are substantially improved, giving a high-quality proton beam which maintained for a longer distance without degradation. The effect is attributed to the radial electric field resulting from the charge due to the hot target electrons propagating along the cone surface. This electric field can effectively suppress the spatial spread of the protons after the expansion of the hot electrons. [ABSTRACT FROM AUTHOR]

Propagation of intense circularly polarized laser pulses in strongly magnetized inhomogeneous plasmas is investigated. It is shown that a left-hand circularly polarized laser pulse propagating up the density gradient of the plasma along the magnetic field is reflected at the left-cutoff density. However, a right-hand circularly polarized laser can penetrate up the density gradient deep into the plasma without cutoff or resonance and turbulently heat the electrons trapped in its wake. Results from particle-incell simulations are in good agreement with that from the theory. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON) causes various toxic effects in human and animals. However, our previous studies have shown that composite antimicrobial peptides (CAP) can have a protective effect in piglets challenged with DON. This study was conducted to evaluate the effect of the CAP GLAM 180# on the metabolism of piglets challenged with DON using a nuclear magnetic resonance (NMR)-based metabolomics approach. A total of 28 individually housed piglets (Duroc × Landrace × Large Yorkshire) weaned at 28 d of age were randomly assigned into 4 treatment groups (7 pigs/treatment) based on a 2 × 2 factorial arrangement that were fed, respectively, a basal diet (NC), basal diet + 0.4% CAP (basal + CAP), basal diet + 4 mg/kg DON (basal + DON), and basal diet + 4 mg/ kg DON + 0.4% CAP (DON + CAP). A 7-d adaptation period was followed by 30 d of treatment. Blood samples were then collected for metabolite analysis by proton NMR (1H-NMR) spectroscopy and liquid chromatography tandem mass spectrometry (LC-MS/MS). The combined results of 1H-NMR spectroscopy and LC-MS/MS showed that DON increased (P < 0.05) the serum concentrations of low-density lipoprotein, glycoprotein, urea, trimethylamine-N-oxide (TMAO), and lactate as well as those of almost all essential AA and some nonessential AA but decreased the concentrations of high-density lipoprotein (HDL), unsaturated lipids, citrate, choline, and fumarate compared with those in NC treatment (P < 0.05). There was a significant interaction effect (P < 0.05) of supplementation with DON and CAP on some metabolites showed that the serum concentrations of HDL, unsaturated lipids, Pro, citrate, and fumarate were greater (P < 0.05) whereas those of glycoprotein, urea, TMAO, Gly, and lactate were lower in the DON + CAP treatment compared with those in the basal + DON treatment (P < 0.05). These findings indicated that DON causes disturbances in AA, lipid, and energy metabolism and that CAP could partially attenuate the above metabolic disturbances induced by DON. [ABSTRACT FROM AUTHOR]

A foil-in-cone target is proposed to enhance stable laser-radiation-pressure-driven proton acceleration by avoiding the beam degradation in whole stage of acceleration. Two and three-dimensional particle-in-cell simulations demonstrate that the guiding cone can substantially improve the spectral and spatial properties of the ion beam and lead to better preservation of the beam quality. This can be attributed to the focusing effect of the radial sheath electric fields formed on the inner walls of the cone, which co-move with the accelerated foil and effectively suppress the undesirable transverse explosion of the foil. It is shown that, by using a transversely Gaussian laser pulse with intensity of ~2.74×1022W/cm², a quasi-monoenergetic proton beam with a peak energy of ~1.5GeV/u, density ~10nc, and transverse size ~1λ0 can be obtained. [ABSTRACT FROM AUTHOR]

The radiation pressure acceleration of protons in the interaction of Gaussian laser pulses and surface modulated targets is examined by multi-dimensional particle-in-cell simulations. It is shown that strong longitudinal quasi-static magnetic field is generated on the modulated surface of the target, which significantly enhances the transverse diffusion of electrons. This is beneficial for suppressing the transverse Rayleigh-Taylor instability. Finally, the surface of the accelerated proton beams becomes smoother than that in the case of the planar target, and a final mono-energetic proton beam is obtained by using the surface modulated target. [ABSTRACT FROM AUTHOR]

A scheme in which carbon ion bunches are accelerated to a high energy and density by a laser pulse (~1021 W/cm²) irradiating cone targets is proposed and investigated using particle-in-cell simulations. The laser pulse is focused by the cone and drives forward an ultrathin foil located at the cone's tip. In the course of the work, best results were obtained employing target configurations combining a low-Z cone with a multispecies foil transversely shaped to match the laser intensity profile. [ABSTRACT FROM AUTHOR]

The enhanced target normal sheath acceleration of ions in laser target interaction via the laser relativistic self-focusing effect is investigated by theoretical analysis and particle-in-cell simulations. The temperature of the hot electrons in the underdense plasma is greatly increased due to the occurrence of resonant absorption, while the electron-betatron-oscillation frequency is close to its witnessed laser frequency [Pukhov et al., Phys. Plasma 6, 2847 (1999)]. While these hot electrons penetrate through the backside solid target, a stronger sheath electric field at the rear surface of the target is induced, which can accelerate the protons to a higher energy. It is also shown that the optimum length of the underdense plasma is approximately equal to the self-focusing distance. [ABSTRACT FROM AUTHOR]

A ferroelectric/multiferroic/ferroelectric sandwiched structure composed by NaBiTiO (NBT) and BiNdFeO (BNF) with a LaNiO buffer layer were prepared by a sol-gel method. X-ray diffraction indicated the NBT/BNF/NBT films exhibited a pure perovskite structure. The average grain size of BNF and NBT/BNF/NBT were found to be 40 and 80 nm, respectively. Interestingly, the electrical and ferroelectric properties such as leakage current, dielectric constant, and remnant polarization of NBT/BNF/NBT sandwiched layer, were superior to those of BNF single film. However, the saturation magnetization of NBT/BNF/NBT sandwiched layer was reduced. Our work suggested the NBT/BNF/NBT sandwiched layer with improved multiferroic characteristics have a promising application for future information storage devices. [ABSTRACT FROM AUTHOR]

By using three-dimensional particle-in-cell simulations with synchrotron radiation damping incorporated, dynamics of ultra-intense laser driven mass-limited foils is presented. When a circularly polarized laser pulse with a peak intensity of ~1022 W/cm2 irradiates a mass-limited nanofoil, electrons are pushed forward collectively and a strong charge separation field forms which acts as a "light sail" and accelerates the protons. When the laser wing parts overtake the foil from the foil boundaries, electrons do a betatron-like oscillation around the center proton bunch. Under some conditions, betatron-like resonance takes place, resulting in energetic circulating electrons. Finally, bright femto-second x rays are emitted in a small cone. It is also shown that the radiation damping does not alter the foil dynamics radically at considered laser intensities. The effects of the transverse foil size and laser polarization on x-ray emission and foil dynamics are also discussed. [ABSTRACT FROM AUTHOR]

Artificial multiferroic superlattices (SL), consisting of BiFeO (16 nm)/BiNaTiO (5 nm) (BFO/BNT SL), were grown on (001) SrTiO single crystal by pulsed laser deposition method. The cross-sectional, surface morphology, and crystallographic structure of BFO/BNT SL and BFO single layer were investigated. It was found that the electrical, ferroelectric, and magnetic properties of BFO/BNT SL exhibit a remarkably enhancement compared with BFO single layer. The influence of BNT buffering layer, lattice strain, and interfaces interplay of the SL structure are supposed to benefit their ferroelectric and ferromagnetic properties. Our works suggested the BFO/BNT SL with an improved multiferroic characteristics have a promising application for the future informational storage devices. [ABSTRACT FROM AUTHOR]

The statistical properties of the user interaction behaviors in a city have great significance for developing the network marketing strategy, promoting personalized service and so on. In this paper, we investigate the interaction property of the users from New Orleans network in the Facebook, and find that one's out-degree and in-degree are approximately the same. In addition, when the number of a user friends is less than 65, the number of their posts would linearly grow with the slope 4.2, but when one user's friends are more than 65, their posts would grow with the slope 2.1. Further, the average link weight is relatively flat when the out-degree ranges from 28 to 65, and before or after the section it is on the rise or in decline, respectively, from which we can conclude that one could not maintain stable and meaningful relationships with more than 65 people in a single city. We present a null model to reshuffle the network to guarantee that the empirical results are not obtained by accident. The result obtained after reshuffling suggests that there exists a limit that restricts people's social activities. [ABSTRACT FROM AUTHOR]

Hemispherical electron plasma waves generated from ultraintense laser interacting with a solid target having a subcritical preplasma is studied using particle-in-cell simulation. As the laser pulse propagates inside the preplasma, it becomes self-focused due to the response of the plasma electrons to the ponderomotive force. The electrons are mainly heated via betatron resonance absorption and their thermal energy can become higher than the ponderomotive energy. The hot electrons easily penetrate through the thin solid target and appear behind it as periodic hemispherical shell-like layers separated by the laser wavelength. [ABSTRACT FROM PUBLISHER]

Existing perceptual researches on stereoscopic image mainly focus on proving the effectiveness of binocular suppression theory in reducing bandwidth during asymmetrical coding. However, they care little about the threshold below which the phenomena exist. To determine the threshold as visible in the asymmetrical stereoscopic image coding, the relationship between visibility threshold and coding parameter or objective quality under practical viewing conditions is investigated in this paper. Perceptual experiments are designed by using the paired comparison methods. Experimental results show that the visible threshold is dependent on stereoscopic image content, coding parameter and objective quality of the left (dominant) view in asymmetrical stereoscopic image coding. Furthermore, we model the visible threshold as a linear function of the quantisation parameter of the left (dominant) view for asymmetrical coding. Then based on the model, we build a looking-up table for practical coding. The concise linear model can serve as an upper bound for controlling perceived quality of asymmetrical coding. [ABSTRACT FROM AUTHOR]

Energetic divergent proton beams can be generated in the interaction of ultra-intense laser pulses with solid-density foil targets via target normal sheath acceleration (TNSA). In this paper, a scheme using a capillary to reduce the proton beam divergence is proposed. By two-dimensional particle-in-cell (PIC) simulations, it is shown that strong transverse electric and magnetic fields rapidly grow at the inner surface of the capillary when the laser-driven hot electrons propagate through the target and into the capillary. The spontaneous magnetic field collimates the electron flow, and the ions dragged from the capillary wall by hot electrons neutralize the negative charge and thus restrain the transverse extension of the sheath field set up by electrons. The proton beam divergence, which is mainly determined by the accelerating sheath field, is therefore reduced by the transverse limitation of the sheath field in the capillary. [ABSTRACT FROM PUBLISHER]

Three-dimensional (3D) video technologies are becoming increasingly popular, as they can provide high quality and immersive experience to end users, where depth maps are employed to generate the virtual views by depth-image-based rendering technique. However, how to reduce the compression and rendering complexities for depth maps while maintaining high rendering quality is still unresolved. In this study, a novel depth map compression and depth-aided view rendering method is proposed. In the proposed method, depth maps are represented with different layers and compressed with different macroblock-mode decision procedure, and several optimisation techniques, including spatio-temporal consistent warping, colour correction and temporal consistent hole filling are embedded into the view rendering framework. Experimental results show that compared with the traditional method, the proposed method can reduce more than 79% compression computational complexity and more than 45% rendering computational complexity, while maintaining high rendering quality. [ABSTRACT FROM AUTHOR]