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Mixed hierarchical lanthanide metal-organic framework (Ln-MOF) with core-shell structure has been acquired via a solution-mediated epitaxial growth method, retaining the spatially segregated structure of network and domain fluorescence property. The excellent heterostructured characteristics of Ln-MOFs enable the effective electron modulation, multiple energy transfer and thereby remarkably increase recognizing and sensing capacity in phosphate (Ps) or adenosine triphosphate (ATP). Ln3+ centers coupled with Ps or ATP could trigger a decrease in fluorescence of Ln3+, and further interrupt original fluorescence intensity ratio of Tb3+/Eu3+ (I 545 /I 616) to shape the ratiometric fluorescent register. The optimized Tb/Eu-MOF with Tb/Eu ratio of 1:1 presented good linearity responsive to Ps and ATP with lower detection limit of 84.1 nM and 121.4 nM, respectively. Meanwhile, the interference and toxicity experiments have confirmed its high selectivity and high biocompatibility. Thus, the probe could be applied to detect Ps in real environmental water and biologically imaging ATP in Hela cells. This has provided a new strategy to construct Ln-system heterojunction with multiplexed luminescence selectivity and sensitivity in substance detection. • The Tb/Eu-MOF ratiometric fluorescence sensor efficiently detects PO43- and ATP system with lower LOD. • It could be used to detect PO43- in real environmental water and biologically imaging ATP in Hela cells. • DFT and in-situ XPS confirmed the energy transfer model and detection mechanism. [ABSTRACT FROM AUTHOR]

Chaos is an important dynamic feature, which generally occurs in deterministic and stochastic nonlinear systems and is an inherent characteristic that is ubiquitous. Many difficulties have been solved and new research perspectives have been provided in many fields. The control of chaos is another problem that has been studied. In recent years, a recurrent neural network has emerged, which is widely used to solve many problems in nonlinear dynamics and has fast and accurate computational speed. In this paper, we employ reservoir computing to control chaos in dynamic systems. The results show that the reservoir calculation algorithm with a control term can control the chaotic phenomenon in a dynamic system. Meanwhile, the method is applicable to dynamic systems with random noise. In addition, we investigate the problem of different values for neurons and leakage rates in the algorithm. The findings indicate that the performance of machine learning techniques can be improved by appropriately constructing neural networks. [ABSTRACT FROM AUTHOR]

• Efficacy of an oral kisspeptin recombinant vaccine on the reproductive physiology and behavior of ram lambs was proposed. • Recombinant (pKS-asd) plasmid was electrically transfected to Salmonella enterica serovar Choleraesuis strain (C500). • Oral vaccine (C500/pKS-asd and C500/pVAX-asd) for treatment and control, respectively was prepared and received 5 × 1010 CFU/ml. • Significantly higher anti-kisspeptin and lower serum concentration levels were detected in the treatment group. The KISS1 gene product, kisspeptin, stimulates gonadotrophic steroid hormone (GNRH) neuronal signaling through the G-protein coupled receptor, kiss1r. Disturbance of this signaling pathway causes hypogonadotropic hypogonadism in mammals. As part of this cutting-edge research project, we analyzed the efficacy of an oral kisspeptin recombinant vaccine on the reproductive physiology and behavior of ram lambs. Ten 56-day old ram lambs were randomly divided into treatment and control groups to receive the experimental recombinant vaccines, C500/pKS-asd or C500/pVAX-asd (aspartate-β semialdehyde dehydrogenase), respectively. The vaccines were orally administered at day 0, 28 and 56 and blood samples were taken and scrotal circumference data recorded at 14-day intervals (days 0, 14, 28, 42, 56, 70, and 84). At the end of the experimental period, day 98, sexual behaviors were assessed, scrotal circumferences were measured, and blood samples were collected. Testicular samples were also collected after the animals were sacrificed. Anti-kisspeptin antibody and testosterone serum levels were measured by indirect ELISA. Results demonstrated that the levels of anti-kisspeptin antibodies were significantly higher in the treatment group compared to controls (P < 0.05, P < 0.01 and P < 0.001). However, serum testosterone levels were lower in the treatment group (P < 0.01). Interestingly, vaccine administration contributed to a significant reduction (P < 0.01) in sexual behavior propensity. These results suggest that the kisspeptin recombinant oral vaccine regulates and inhibits the reproductive physiology and behavior of ram lambs. [ABSTRACT FROM AUTHOR]

The current study aimed to evaluate the possible role of microRNA (miR)-202 in the development of oral cancer. First, miR-202 levels were found to be decreased in the serum and tissues of oral cancer patients compared with healthy controls. Receiver operating characteristic analysis was carried out to explore the diagnostic value of serum miR-202 for oral cancer. Overexpression of miR-202 significantly decreased the migratory capacity of SCC-9 cells, while inhibition of miR-202 markedly increased the migratory capacity of SCC-9 cells. Moreover, the invasive capacity was decreased in SCC-9 cells transfected with an miR-202 mimic. In addition, the invasive capacity was enhanced in SCC-9 cells transfected with an miR-202 inhibitor. A dual luciferase reporter assay showed that overexpression of miR-202 markedly suppressed the relative luciferase activity of the pmirGLO-SP1-3′untranslated region. Overexpression of miR-202 suppressed the protein level of Sp1, but inhibition of miR-202 markedly enhanced the protein expression of Sp1. Inhibition of miR-202 enhanced the phosphorylation of protein kinase B. Additionally, the correlations between the expression levels of Sp1 and miR-202 and the clinicopathological factors of oral cancer were analyzed. The results showed that patients with high expression of Sp1 and miR-202 progressed to earlier clinical stages, had deeper infiltration depths and were more prone to lymph node metastasis compared with the healthy controls. In conclusion, the current study presented novel data indicating that decreased miR-202 enhanced the progression of oral cancer via Sp1. [ABSTRACT FROM AUTHOR]

Canker pathogens cause necrosis of the phloem, but in many host/pathogen systems, they also cause canopy dieback, which implicates xylem, not phloem dysfunction. We hypothesize that this dieback distal to the canker is caused by water stress resulting from the lack of a phloem-to-xylem connection, which in a healthy plant would allow delivery of nonstructural carbohydrates (NSCs) and water inward to aid in xylem embolism refilling. We tested several components of this hypothesis in the host/pathogen system Corylus avellana L./ Anisogramma anomala (Peck) E. Müll (Eastern filbert blight). Cankers were non-girdling and usually ≥0.1 m long. As expected, healthy controls had higher specific conductivity (K s) than diseased stems, but unexpectedly, had similar moisture content (m.c.), showing that the lower K s did not result from more embolisms in the diseased stems. Moreover, manipulations that removed cambium and phloem to simulate a canker, or that shaded stems to lower NSCs, did not result in lower K s or m.c. than controls. The outer millimeter of xylem adjacent to a canker had infrequent tyloses and/or fungal hyphae in many but not all samples, and dye studies showed little xylem water transport in that region, but the incidence of these blockages was insufficient to cause the observed 19% decrease in K s. Healthy stems had higher m.c. than diseased stems above the canker (or analogous) location and were longer for the same leaf weight, suggestive of water stress in the upper portion of diseased stems. These results suggest that dieback distal to cankers in this system results from the bottleneck in water transport in the region adjacent to a canker, but did not find evidence to support the requirement of a phloem-to-xylem connection for continued water transport. [ABSTRACT FROM AUTHOR]

• The circadian clock is ubiquitous and conserved across a wide range of species. • The circadian clock is inherently linked to the mechanism of aging. • Breakdown of the circadian system is associated with age-related functional decline. • Aging impairs different components of the clock at central and peripheral levels. • Reinforcement of the clock is a possible strategy to benefit health and longevity. The circadian clock drives periodic oscillations at different levels of an organism from genes to behavior. This timing system is highly conserved across species from insects to mammals and human beings. The question of how the circadian clock is involved in the aging process continues to attract more attention. We aim to characterize the detrimental impact of aging on the circadian clock organization. We review studies on different components of the circadian clock at the central and periperal levels, and their changes in aged rodents and humans, and the fruit fly Drosophila. Intracellular signaling, cellular activity and intercellular coupling in the central pacemaker have been found to decline with advancing age. Evidence of degradation of the molecular clockwork reflected by clock gene expression in both central and peripheral oscillators due to aging is inadequate. The findings on age-associated molecular and functional changes of peripheral clocks are mixed. We conclude that aging can affect the circadian clock organization at various levels, and the impairment of the central network may be a fundamental mechanism of circadian disruption seen in aged species. [ABSTRACT FROM AUTHOR]

Bimetallic zeolitic imidazolate framework (NiCo-ZIF)-templated NiCoS-porous carbon (PC) at only 0.2 at% exhibited versatile effects on the morphology as well as the photocatalytic hydrogen performance of TiO2 nanocrystals. It not only refined the TiO2 particle size during the post-annealing process at high temperature, but also transformed into a highly conductive NiCoS-PC cocatalyst. The conductive PC improved the transport of the charge carriers, and increased the numbers of exposed active sites by confining the particle size of TiO2. Furthermore, the well-dispersed NiCoS could be regarded as a hydrogen production cocatalyst on account of its improvement of the electrochemical hydrogen evolution reaction (HER). Consequently, the optimal TiO2–NiCoS-PC exhibited an extremely high photocatalytic hydrogen production rate of 1.29 mmol h−1 g−1, which is 64.5 and 2.4 times those of pristine TiO2 and commercial P25, respectively. This work provides an effective way of developing high-performance MOF-templated nanoporous photocatalysts. [ABSTRACT FROM AUTHOR]

Iron acetylacetonate (Fe(acac) 3) modified polymethylsilsesquioxane (PMS), simplified as PMS(Fe), was firstly obtained from PMS and Fe(acac) 3 via the condensation reaction. Multi-walled carbon nanotubes (MWCNTs) were then introduced to fabricate the corresponding MWCNTs/SiC nanocrystals/amorphous SiOC ceramic composites via pyrolyzed process. Owing to the catalytic effect of iron and heterogeneous nucleation promoted by MWCNTs, SiC nanocrystals were separated from SiOC amorphous ceramic matrix under 1400 °C. When the mass fraction of MWCNTs was 9 wt%, the obtained MWCNTs/SiC nanocrystals/amorphous SiOC ceramic composite (C9) demonstrated high microwave-absorbing properties. The minimum reflection loss (RL min) and effective absorption bandwidth (EBA) of the obtained C9 at X-band (8.2–12.4) reached −61.8 dB and 2.6 GHz (a thickness of 2.19 mm), respectively. Compared with other polymer-derived ceramics (PDCs), the RL min was higher and the required thickness was thinner. This excellent microwave-absorbing property was due to the interfacial polarization relaxation generated between nanocrystals (MWCNTs & SiC) and amorphous SiOC, and the formed complete conductive networks inside the ceramic composites. [ABSTRACT FROM AUTHOR]

The importance of the circadian clock for the control of behavior and physiology is well established but how and when it develops is not fully understood. Here the initial expression pattern of the key clock gene period was recorded in Drosophila from embryos in vivo, using transgenic luciferase reporters. PERIOD expression in the presumptive central-clock dorsal neurons started to oscillate in the embryo in constant darkness. In behavioral experiments, a single 12-h light pulse given during the embryonic stage synchronized adult activity rhythms, implying the early development of entrainment mechanisms. These findings suggest that the central clock is functional already during embryogenesis. In contrast to central brain expression, PERIOD in the peripheral cells or their precursors increased during the embryonic stage and peaked during the pupal stage without showing circadian oscillations. Its rhythmic expression only initiated in the adult. We conclude that cyclic expression of PERIOD in the central-clock neurons starts in the embryo, presumably in the dorsal neurons or their precursors. It is not until shortly after eclosion when cyclic and synchronized expression of PERIOD in peripheral tissues commences throughout the animal. [ABSTRACT FROM AUTHOR]

Different from classic polyelectrolytes, poly(ionic liquid)s (PILs) bearing hydrophobic counterions show high electrorheological (ER) effect in dry state. This opens a way to develop new generation of anhydrous polyelectrolyte ER fluids. However, PILs with linear backbone are limited in practical applications due to low glass transition temperature. Crosslinking is an effective method to overcome this problem but the structure-property relationship in crosslinked PIL ER system is not fully understood. Herein, a family of self-crosslinked poly(bis-vinylimidazolium bis(trifluoromethane sulfonylimide))-based PILs with different length of alkyl spacer (P[C n DVIM][TFSI]) were synthesized. The influence of alkyl spacer length on ER effect was studied and the influence mechanism was analyzed by combination of rheology, dielectric spectroscopy and X-ray scattering measurements. It shows that as alkyl spacer length increases, the ER effect increases but the working temperature range becomes narrow. This is related to the fact that the length variation of alkyl spacer alters the mesh size of crosslinking network of P[C n DVIM][TFSI], which further influences the transport dynamic of mobile counterions and ion motion-induced interfacial polarization. Self-crosslinked poly(ionic liquid) particles with different length of alkyl spacer are synthesized, which show increased ER effect but narrowed working temperature range with increasing alkyl spacer length because increasing the mesh size of crosslinking network decreases the potential energy barrier for ion transport and ion motion-induced interfacial polarization but easily causes current leakage at high temperature. Image 1 • Self-crosslinked PILs with different length of alkyl spacer are synthesized. • As spacer length increases, ER effect of PILs increases but working temperature range becomes narrow. • Spacer length influence is because mesh size of crosslinking network influences ion transport and interfacial polarization. [ABSTRACT FROM AUTHOR]

• Nitrogen and phosphorus codoped carbon-based catalyst was successfully prepared. • Catalysts with NP-C600 gave excellent activity and stability for acetylene hydrochlorination. • The conversion of C 2 H 2 over NP-C600 is almost identical to that over Au/C. • Phosphorus atoms bonded with nitrogen in a pyridine structure are the active sites for the best-performing NP-C600 catalyst. Catalyzed acetylene hydrochlorination for vinyl chloride monomer (VCM) production is of great industrial importance, as VCM is the precursor for polyvinyl chloride. Carbon-based materials have recently been proposed as environmentally friendly and cost-efficient substitutes for highly toxic mercuric chloride catalyst, which is currently used for VCM manufacture. However, their practical application has been limited because of their relatively low reactivity, due to the lack of efficient active sites. Structural engineering of carbon-based materials has been proved a powerful strategy for tuning their physical and chemical properties, which are directly related to their catalytic properties. Here we present a novel and highly active nitrogen- and phosphorus-codoped carbon-based catalyst prepared using 1-ethylsulfonate-3-methylimidazolium dihydrogen phosphate [ESO 3 HMim+H 2 PO 4 −] as a phosphorus source and 1-ethyl-3-methylimidazolium dicyanamide [EMim]+N(CN) 2 −] as a nitrogen source, which has shown unexpectedly high acetylene hydrochlorination activity with space-time yield comparable to that of some well-developed Au-based catalysts. Experimental observations in combination with density functional theory calculations demonstrated that phosphorus atoms bonded with nitrogen in the pyridine structure are the active sites for the best-performing NP-C600 catalyst. This work provides a promising method of structure tuning of carbon-based metal-free materials to effectively optimize their catalytic mechanism and applications. [ABSTRACT FROM AUTHOR]

Design and synthesis of high-efficiency and low-cost photocatalysts is essential for converting solar energy into clean hydrogen energy. Herein, we report a novel TiO2 nanocrystal photocatalyst confined by ZIF-67-templated porous CoSx, with conductive Ti3C2 boosting the transport efficiency of the charge carriers. TiO2–CoSx and TiO2–Ti3C2–CoSx exhibit a photocatalytic H2-production activity 2.8 and 5.8 times larger than that of pristine TiO2, respectively, because of the existence of the highly porous MOF-templated CoSx hydrogen evolution reaction cocatalyst and highly conductive Ti3C2. This study will provide a practical reference for the design and preparation of efficient photocatalysts with high transport and utilization efficiency of charge carriers. [ABSTRACT FROM AUTHOR]

Abstract We present a numerical scheme that preserves the total energy and the entropy production rate, termed the energy and entropy production rate preserving scheme, for a general class of thermodynamically consistent phase field models for dendritic crystal growth derived from the first and second law of thermodynamics. The scheme is second order in time, linear and energy and entropy production rate preserving for any time steps. The scheme is first discretized in time aided by the energy quadratization (EQ) method and then in space using compact finite difference methods. The linear system resulting from the scheme is shown to be uniquely solvable at both the semi-discrete and the fully discrete level. Mesh refinement tests are performed to show the second-order time convergence rate in the scheme. Several numerical examples of dendritic crystal growth are provided to demonstrate the accuracy and efficiency of the scheme. The effects of various model parameters on growth patterns of the crystal are further investigated in details with the numerical solver. The approach to developing the energy and entropy production rate-preserving numerical scheme proposed in this study is so general that it can be applied to a wide range of thermodynamically consistent models not limited to phase field models. Highlights • Derived a class of thermodynamically consistent phase field model for nonisothermal binary material systems. • Designed a set of second order, linear numerical schemes that respect the two thermodynamic laws at the discrete level. • Several benchmarking numerical examples of dentritic crystal growth are presented after the scheme is implemented on GPUs. [ABSTRACT FROM AUTHOR]

A hybrid of ZIF-8 with CdS nanorods could increase the transport efficiency of photo-generated charge carriers and the surface area. Notably, through doping Zn ions with a transition metal, in this work, we fabricated a bimetallic ZnM-ZIF (M = Ni, Cu, or Co)-encapsulated CdS nanorod heterostructure for the first time. Compared with ZIF-8, the bimetallic ZIF exhibited a modulated structure, flat band position, and lower overpotential for the hydrogen evolution reaction. ZnM-ZIF not only improved the transfer of water and light, but also boosted the separation of charge carriers. Consequently, the optimized CdS-ZnM-ZIF samples with Cu, Ni, and Co doping showed corresponding photocatalytic hydrogen activities 44, 92, and 59 times larger than that of pristine CdS nanorods. This work provides a new method for better utilization of porous MOF crystals for photocatalysts. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Supported-ionic-liquid-phases as stabilizer of Pd complex active phase. • Different Pd loadings were screened to identify an optimized Pd-based supported-ionic-liquid-phase catalyst. • The catalyst showed superior catalytic activity for acetylene hydrochlorination. • The catalyst displayed stable performance after running for 500 h. • The enhanced catalytic stability may attribute to the confinement of Pd complex. Abstract Vinyl chloride monomer (VCM) is an important platform molecule for the manufacture of polyvinyl chloride (PVC) via the direct hydrochlorination route from acetylene. However it is plagued by the toxicity of the mercury chloride (HgCl 2) catalyst. Here we show that a 0.5Pd-10IL/AC catalyst, working as an environmentally friendly and highly efficient catalyst in supported-ionic-liquid-phase (SILP) system, is an plausible alternative for the commercially used HgCl 2 catalyst for acetylene hydrochlorination. It performs higher activity and more stable conversion than ionic liquid (IL)-free 0.5Pd/AC catalyst during a 10 h reaction. Furthermore, the low-loading 0.15Pd-10IL/AC catalyst demonstrates a stable catalytic performance with a negligible loss of C 2 H 2 conversion after 500 h under typical industrial reaction conditions. After careful characterization of the catalysts and additional catalytic tests, we ascribe the IL influence on the activity and stability of the catalysts to the stabilization and dispersion of active Pd species in the IL layer, the possible coordination of the IL to the Pd atoms, and the confinement of Pd complexes within the pores supports. This efficient and stable non-mercury catalyst provides an opportunity for green route to large-scale vinyl chloride production. [ABSTRACT FROM AUTHOR]

The present article considers the ways in which written enunciations are superimposed upon painted enunciations, and the ways in which the former stratify, modify and break the unity of the latter. We take as our examples some paintings by the French painter Robert Combas, a leading light in the 'Figuration libre' movement of the 1980s, which sought to invest painting with narrativity. Combas frequently uses writing in his pictorial creations. The written word introduces a new level of enunciation, an alternative voice, a different world – which, taken in and of itself, constitutes an autonomous entity, and placed in parallel to the image, creates a sort of polyphony in which the two sometimes clash. We analyse writing within Combas's paintings, and the 'paratexts' that accompany these, interrogating the relationship between text and image in the works' different enunciatory levels. [ABSTRACT FROM AUTHOR]

Ardehali (Phys. Rev. A, 46, 5375 (1992). 10.1103/PhysRevA.46.5375) derived a Bell-type inequality for an n-particle system in a Greenberger–Horne–Zeilinger (GHZ) state. This inequality helps relax the detection efficiencies required for closing the detection loophole in Bell tests. Coffman et al. (Phys. Rev. A, 61, 052306 (2000). doi:10.1103/PhysRevA.61.052306) gave a simplified form of tripartite entanglement of three-qubit pure states. We use theory and experiment to investigate both results using three-qubit GHZ states with different intensities of bit-flip noise. The purpose of our work is to relate the Ardehali inequality and the tripartite concurrence of the tripartite GHZ states in a noisy environment. Our results show that the experimental values are quite consistent with theoretical predictions for three-qubit GHZ states in a bit-flip noisy environment. [ABSTRACT FROM AUTHOR]

Abstract A high uniformity and broad bandwidth Y junction optical beam splitter is proposed and analyzed in this paper based on silicon-on-insulator platform. By replacing the uniform branch with the multimode tapered branch, the bandwidth and the power uniformity of two output ports are improved prominently. Furthermore, the sensitivity to fabrication accuracy is reduced by widening the splitting angle. The simulation and the experimental results confirm that the bandwidth is larger than 100 nm, the power uniformity of two output ports is enhanced 4 dB, whereas the insertion loss is less than 0.6 dB and the return loss is larger than 26 dB, respectively. [ABSTRACT FROM AUTHOR]

Nitrogen‐doped carbons supported gold catalysts has attracted much attention in a broad range of applications. However, co‐existence of multiple nitrogen species which may have vastly different effect on the gold‐based catalysts, has limited the development of an ideal nitrogen‐doped carbon support. Herein, we have demonstrated that by addition of sulfur species, selective formation of pyrrolic nitrogen against pyridinic nitrogen can be achieved for pyrrolic nitrogen doped carbon support. The gold catalysts synthesized from the pyrrolic nitrogen doped carbon support produced using ionic liquid‐assisted synthetic strategy (Au/N, S‐AC‐700), exhibited excellent catalytic activity and stability for hydrochlorination of acetylene. The outstanding performance was attributed to the π electrons transferred from pyrrolic nitrogen to Au (III) center, which could increase the electron density of Au hence facilitate the adsorption of hydrogen chloride on the catalyst. Green economy? Carbon with surface‐enriched nitrogen and sulfur supported Au catalysts was developed for acetylene hydrochlorination. The presence of sulfur species on the carbon surface inhibited the formation of pyridinic N which was not necessary for the hydrochlorination of acetylene. [ABSTRACT FROM AUTHOR]

The study was intended to investigate the protective effects of emodin against cell injury and inflammation in AR42J cells. We determined trypsin and lipase activity, intracellular ROS and MMP using specific assay kits. The related protein expression and TNF-α and IL-6 in the medium were assayed by Western blot and ELISA kits. Results showed that emodin could protect AR42J cells against cell injury caused by cerulein and lipopolysaccharide which were possibly associated with inhibition of mitochondrial damage, ROS production, and then significantly inhibited ROS-mediated pathway, and ameliorated pancreatic cells injury by depleting the levels of inflammatory cytokines. [ABSTRACT FROM AUTHOR]

Dichroism refers to the differential absorption of a material for different polarized waves and has important applications in polarimetry and optical wavefront manipulation. The coexistence of strong linear and circular dichroism at thin optical interfaces is usually challenging due to the weak chiral anisotropy in natural materials. Here, we investigate the spatially dispersive dichroism of bianisotropic metamirror, in which giant linear and circular dichroism can be achieved simultaneously. By covering the metallic mirror with an array of bianisotropic resonators, specific linearly and circularly polarized waves can be largely absorbed under normal and oblique incidences, respectively. This intriguing phenomenon is attributed to the anisotropic magneto-electric coupling, that is, the handedness and the strength of the equivalent transverse electric surface current are determined by the angle of incidence. Furthermore, dual-band and hybrid-chirality metamirrors for asymmetric spin reflection have been realized by adjusting the geometries and arrangement of the bianisotropic resonators. The overall thickness of the bianisotropic metamirror is only 1/50 of the wavelength and thus highly suitable for on-chip integration. Our findings may provide an alternative approach towards multifunctional optical mirrors, signal detectors, chiral imaging devices, and molecular analyzers. [ABSTRACT FROM AUTHOR]

In this paper, we consider numerical approximations for the viscous Cahn–Hilliard equation with hyperbolic relaxation. This type of equations processes energy-dissipative structure. The main challenge in solving such a diffusive system numerically is how to develop high order temporal discretization for the hyperbolic and nonlinear terms, allowing large time-marching step, while preserving the energy stability, i.e. the energy dissipative structure at the time-discrete level. We resolve this issue by developing two second-order time-marching schemes using the recently developed “Invariant Energy Quadratization” approach where all nonlinear terms are discretized semi-explicitly. In each time step, one only needs to solve a symmetric positive definite (SPD) linear system. All the proposed schemes are rigorously proven to be unconditionally energy stable, and the second-order convergence in time has been verified by time step refinement tests numerically. Various 2D and 3D numerical simulations are presented to demonstrate the stability, accuracy, and efficiency of the proposed schemes. [ABSTRACT FROM AUTHOR]

Abstract Two new terpenoids, named biperovskatone B (1) and 1α- hydroxyl demethylsalvicanol quinine (2), were isolated from the cultured Perovskia atriplicifolia. Their structures were elucidated by comprehensive analyses of the MS, IR, 1D and 2D NMR spectra. Compound 1 was a novel diterpenoid dimer, containing two different rearranged 9(10 → 20)-abeoabietane type diterpenoid fragments. Compound 2 was a new icetexane diterpenoid with characteristic ortho -quinone carbonyl groups. Both compounds were assayed for their anti-HBV activity in vitro. Results suggested compounds 1 and 2 showed noticeable anti- anti-HBV activity, inhibiting the replication of HBV DNA with IC 50 values of 10.78 and 8.61 μM, respectively. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

We develop two linear, second order energy stable schemes for solving the governing system of partial differential equations of a hydrodynamic phase field model of binary fluid mixtures. We first apply the Fourier pseudo-spectral approximation to the partial differential equations in space to obtain a semi-discrete, time-dependent, ordinary differential and algebraic equation (DAE) system, which preserves the energy dissipation law at the semi-discrete level. Then, we discretize the DAE system by the Crank-Nicolson (CN) and the second-order backward differentiation/extrapolation (BDF/EP) method in time, respectively, to obtain two fully discrete systems. We show that the CN method preserves the energy dissipation law while the BDF/EP method does not preserve it exactly but respects the energy dissipation property of the hydrodynamic model. The two new fully discrete schemes are linear, unconditional stable, second order accurate in time and high order in space, and uniquely solvable as linear systems. Numerical examples are presented to show the convergence property as well as the efficiency and accuracy of the new schemes in simulating mixing dynamics of binary polymeric solutions. [ABSTRACT FROM AUTHOR]

A simple and effective photochemical method was developed for cross-linking of polymer gate dielectrics. Laborious synthetic processes for functionalizing polymer dielectrics with photo-cross-linkable groups were avoided. The photo-cross-linker, BBP-4, was added into host polymers by simple solution blending process, which was capable of abstracting hydrogen atoms from polymers containing active C―H groups upon exposure to ultraviolet (UV) radiation. The cross-linking can be completed with a relatively long wavelength UV light (365 nm). The approach has been applied to methacrylate and styrenic polymers such as commercial poly(methylmethacrylate) (PMMA), poly(iso-butylmethacrylate) (PiBMA) and poly(4-methylstyrene) (PMS). The cross-linked networks enhanced dielectric properties and solvent resistance of the thin films. The bottom-gate organic field-effect transistors (OFETs) through all solution processes on plastic substrate were fabricated. The OFET devices showed low voltage operation and steep subthreshold swing at relatively small gate dielectric capacitance. [ABSTRACT FROM AUTHOR]

Schisandra Chinensis (Turcz.) Baill. is a long-term used traditional Chinese medicine with the functions of tonifying the kidney and calming the heart, tonifying qi and engendering fluid. It can be used to treat insomnia and dreaminess, spermatorrhea, coughs, as well as liver and kidney deficiency of Yin or Yang Syndrome. Modern pharmacological studies have shown that Schisandra Chinensis regulates host immunity and exhibits anti-cancer, antiviral and liver-protecting effects. However, the specific mechanism by which Schisandra Chinensis modulates antiviral immunity is unknown. We sought to explore the therapeutic effect of the active components of Schisandra Chinensis on anti-viral immunity and further investigate the underlying mechanism. Immunoblotting, quantitative real-time PCR, enzyme-linked immunosorbent assay, immunofluorescence, and immunoprecipitation were used to investigate the effect of schisandrin C (SC), one of the most abundant and biologically active components of Schisandra Chinensis , on the activation of cGAS-STING signaling pathway and the underlying mechanism. In addition, CMA-mediated STING activation and hydrodynamic injection-mediated HBV-replicating mouse model were used to investigate the effect of SC on the activation of STING signaling pathway and its antiviral effect in vivo. SC promoted cGAS-STING pathway activation, accompanied by increased production of interferon β (IFN β) and downstream gene expression. Moreover, SC also exerted anti-HBV effects, reducing HBeAg, HBcAg, HBsAg, and HBV DNA levels in hydrodynamic injection-mediated HBV-replicating mouse model and elevating the production of IFN β and expression of interferon-stimulated genes (IFIT1, ISG15, and CXCL10). Mechanistically, SC could facilitate the interaction between TANK-binding kinase 1 (TBK1) and STING, which is important for IRF3 phosphorylation and production of IFN β. Our study confirmed that SC enhances cGAS-STING pathway activation and inhibits HBV replication, as well as provides clues for chronic hepatitis B and other infectious diseases treated by SC. [Display omitted] • Schisandrin C (SC) promotes cGAS-STING pathway activation. • SC promotes cGAS-STING pathway activation by facilitating the interaction between TBK1 and STING. • SC markedly attenuates hepatitis B virus replication in vivo and promotes the expression of IFN β and ISGs. [ABSTRACT FROM AUTHOR]

The structural characteristics of two water-extracted pectic polysaccharides from Fructus aurantii were investigated, and the impacts of their structures on the emulsifying stability were evaluated. FWP-60 (extracted by cold water and followed 60 % ethanol precipitation) and FHWP-50 (extracted by hot water and followed 50 % ethanol precipitation) were both high methyl-esterified pectins, which were composed of homogalacturonan (HG) and highly branched rhamnogalacturonan I (RG-I) regions. The weight-average molecular weight, methyl-esterification degree (DM) and HG/RG-I ratio of FWP-60 were 1200 kDa, 66.39 % and 4.45, respectively, which were 781 kDa, 79.10 % and 1.95 for FHWP-50. The methylation and NMR analysis of FWP-60 and FHWP-50 demonstrated that the main backbone consisted of different molar ratios of →4)-α-Gal p A-(1 → and →4)-α-Gal p A-6- O -methyl-(1 →, and the side chains contained arabinan and galactan. Moreover, the emulsifying properties of FWP-60 and FHWP-50 were discussed. Compared with FHWP-50, FWP-60 had better emulsion stability. Overall, pectin had a linear HG domain and a small number of RG-I domain with short side chains to facilitate the stabilization of emulsions in Fructus aurantii. A comprehensive knowledge of the structure characteristic and emulsifying property would enable us to provide more information and theoretical guidance for the structure and emulsion preparation of Fructus aurantii pectic polysaccharides. • Two pectic polysaccharides (FWP-60 and FHWP-50) were purified from Fructus aurantii. • Both FWP-60 and FHWP-50 were composed of HG and RG-I regions. • FWP-60 and FHWP-50 emulsions exhibited the different stability behaviors. • The effect of structures on emulsifying properties of FWP-60 and FHWP-50 were discussed. [ABSTRACT FROM AUTHOR]

The structural characteristics of two water-extracted pectic polysaccharides from Fructus aurantii were investigated, and the impacts of their structures on the emulsifying stability were evaluated. FWP-60 (extracted by cold water and followed 60 % ethanol precipitation) and FHWP-50 (extracted by hot water and followed 50 % ethanol precipitation) were both high methyl-esterified pectins, which were composed of homogalacturonan (HG) and highly branched rhamnogalacturonan I (RG-I) regions. The weight-average molecular weight, methyl-esterification degree (DM) and HG/RG-I ratio of FWP-60 were 1200 kDa, 66.39 % and 4.45, respectively, which were 781 kDa, 79.10 % and 1.95 for FHWP-50. The methylation and NMR analysis of FWP-60 and FHWP-50 demonstrated that the main backbone consisted of different molar ratios of →4)-α-Gal p A-(1 → and →4)-α-Gal p A-6- O -methyl-(1 →, and the side chains contained arabinan and galactan. Moreover, the emulsifying properties of FWP-60 and FHWP-50 were discussed. Compared with FHWP-50, FWP-60 had better emulsion stability. Overall, pectin had a linear HG domain and a small number of RG-I domain with short side chains to facilitate the stabilization of emulsions in Fructus aurantii. A comprehensive knowledge of the structure characteristic and emulsifying property would enable us to provide more information and theoretical guidance for the structure and emulsion preparation of Fructus aurantii pectic polysaccharides. • Two pectic polysaccharides (FWP-60 and FHWP-50) were purified from Fructus aurantii. • Both FWP-60 and FHWP-50 were composed of HG and RG-I regions. • FWP-60 and FHWP-50 emulsions exhibited the different stability behaviors. • The effect of structures on emulsifying properties of FWP-60 and FHWP-50 were discussed. [ABSTRACT FROM AUTHOR]

• A new DPC algorithm for uneven density datasets is proposed. • A new local density calculation method based on fuzzy neighborhood is designed. • A new allocation strategy based on weighted shared nearest neighbor is proposed. • The new DPC algorithm has excellent clustering accuracy for different types of datasets. Uneven density data refers to data with a certain difference in sample density between clusters. The local density of density peaks clustering algorithm (DPC) does not consider the effect of sample density difference between clusters of uneven density data, which may lead to wrong selection of cluster centers; the algorithm allocation strategy makes it easy to incorrectly allocate samples originally belonging to sparse clusters to dense clusters, which reduces clustering efficiency. In this study, we proposed the density peaks clustering algorithm based on fuzzy and weighted shared neighbor for uneven density datasets (DPC-FWSN). First, a nearest neighbor fuzzy kernel function is obtained by combining K-nearest neighbor and fuzzy neighborhood. Then, local density is redefined by the nearest neighbor fuzzy kernel function. The local density can better characterize the distribution characteristics of the sample by balancing the contribution of sample density in dense and sparse areas, in order to avoid the situation that the sparse cluster does not have a cluster center. Finally, the allocation strategy for weighted shared neighbor similarity is proposed to optimize the sample allocation at the boundary of the sparse cluster. Experiments are performed on IDPC-FA, FKNN-DPC, FNDPC, DPCSA and DPC for uneven density datasets, complex morphologies datasets and real datasets. The clustering results demonstrate that DPC-FWSN effectively handles datasets with uneven density distribution. [ABSTRACT FROM AUTHOR]

Ferrihydrite is a common iron hydroxide in mining environments and arsenic has high adsorption affinity with it. Biological anaerobic reduction of arsenical ferrihydrite represents an aqueous arsenic and colloids release process. Arsenical ferrihydrite was collected from Jiepaiyu As-(Au) Mine area and used to investigate aqueous arsenic (III and V) and the relationship with colloid fractions (Large: <10 μm, medium: <1 μm and small: <10 nm) under sulfate-reducing bacteria (Desulfovibrio vlugaris miyazaki). Different arsenical ferrihydrite solid to solution ratios were investigated by batch experiment. In anaerobic conditions, the highest concentrations of aqueous arsenic(III) and arsenic(V) released into solution per gram arsenical ferrihydrite were on days 2 and 3 for low ratio (9449 μg/L and 8035 μg/L, respectively) and high ratio conditions (13672 μg/L and 7760 μg/L, respectively). Arsenic(III) concentrations with colloids varies the same as for aqueous arsenic(III), increasing from 0 day to 3 days and then decreasing. These colloids contain total iron of 7–563 mg/L, arsenic(III) of 84–3534 μg/L and arsenic(V) of 5082–14520 μg/L. Ferrous (Fe2+) and sulfur (S2-) components are found in the colloids, which their mole ratio is 0.8–8.7. There is considerable difference among mobilization of various colloids. The transportation velocities of these colloids follow this sequence: large > medium > small. These results suggest that biological reduction changes arsenic species and colloid fractions, which affect geochemical mobilization of arsenic. [Display omitted] • Ratios of solid and solution affect arsenic release and species variation for SRB-ferrihydrite system. • Colloids with various size are separated during bio-reduction of ferrihydrite. • Colloids contain iron, arsenic and sulfur. • Large colloid transports more quickly than small colloid due to size exclusion. [ABSTRACT FROM AUTHOR]

Eight undescribed β-bergamotene-type sesquiterpene oliganins A-H (1–8) and one known α-bergamotene-type sesquiterpene (9) were isolated from the leaves and twigs of Illicium oligandrum Merr. & Chun. The structures of compounds 1 – 8 were elucidated by extensive spectroscopic data, and the absolute configurations were determined by using a modified Mosher's method and electronic circular dichroism calculations. The isolates were further evaluated in terms of their anti-inflammatory potential on nitric oxide (NO) generation in lipopolysaccharide-stimulated RAW264.7 and BV2 cells. Compounds 2 and 8 exhibited potent inhibitory effects on the production of NO with IC 50 values ranging from 21.65 to 49.28 μM, which were greater than or comparable to those of dexamethasone (positive control). β-Bergamotene-type sesquiterpenes with an α,β-unsaturated ketone exhibited potential nitric oxide inhibitory effect in LPS-stimulated RAW264.7 and BV2 cells with IC 50 values ranging from 21.65 to 49.28 μM, which were stronger or comparable than those of dexamethasone. [Display omitted] • Eight undescribed β-bergamotene-type sesquiterpenes were isolated from Illicium oligandrum. • The stereochemistry of epimeric isomers was determined by ECD calculations. • Two sesquiterpenes with an α, β-unsaturated ketone exhibited potent NO inhibitory activity. [ABSTRACT FROM AUTHOR]

A novel chemically modified cellulose filter paper (CMCFP) was prepared by a two-step reaction of esterification and thiol-ene click reaction with cellulose filter paper (CFP). The paper based CMCFP extraction material was used to extract amphetamine-type stimulants (ATSs) from water, followed by high-performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-MS/MS) determination. The FT-IR, XPS, and SEM characterizations showed that the modifiers of 3-mercaptopropionic acid and sodium 4-vinylbenzenesulfonate were successfully covalently grafted onto the CFP. The recovery rates of the 7 target ATSs by CMCFP extraction had a maximum value in the pH range of 4.0–7.0. The kinetic experiments indicated that the main adsorption mechanism of CMCFP for ATSs was chemisorption. The adsorption capacity was greater than 37 ng·cm-2. Surface water and wastewater spike experiments revealed that the determination of 7 ATSs by CMCFP extraction coupled with HPLC-MS/MS method had recoveries of 80.5–116%. Meanwhile, the detection limits were 0.40–3.03 ng·L-1, and the linear range was 20–1000 ng·L-1 with relative standard deviations of 2.2–11%. The CMCFP extraction material obtained in this study is environmentally friendly and economical, and has the same good extraction efficiency as the commercial solid phase extraction cartridges. [Display omitted] • A novel chemically modified cellulose filter paper (CMCFP) was prepared. • The CMCFP was used to extract amphetamine-type stimulants (ATSs) from water. • Determination of ATSs in water was established by CMCFP extraction with HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

Poly(ionic liquid)s (PILs) encapsulated nano-SiO 2 composite particles were synthesized by a Pickering emulsion polymerization and used as stimuli-responsive electorheological (ER) particles, which showed enhanced electro-responsive effectiveness and temperature stability. Methacryloxypropyltrimethoxysilane modified nano-SiO 2 particles with size of 15 nm were used as solid surfactant, which could not only help to form emulsion droplets of IL monomer but also immerse into droplets to form nanocomposite particles after polymerization. The morphology of the nanocomposite particles was characterized by scanning electron microscopy and transmission electron microscopy, while the chemical structure was analyzed by thermogravimetric analysis and Fourier transform infrared spectroscopy. Under electric field, ER property of the nanocomposite particles when dispersed in insulating oil was characterized by temperature-modulated rheology. Through comparing with pure PILs particles, we found that introducing nano-SiO 2 into PILs particles could significantly suppress the excessive growth of leaking current density with increasing temperature and improve the electro-responsive ER effectiveness and temperature stability of ER property. Dielectric spectra analysis indicated that nano-SiO 2 could act as cross-linking points to suppress the thermally promoted segment relaxation and improve the activation energy of the ion transport in PILs matrix, and this should be responsible for the enhanced electro-responsive ER effectiveness and temperature stability of PILs encapsulated nano-SiO 2 composite particles. [ABSTRACT FROM AUTHOR]

Constructing hollow mesoporous nanostructures for dispersing catalytically active sites has attracted growing interest. Here, for the first time, Co 3 O 4 hollow nanocages (Co 3 O 4 HNCs) derived from ZIF-67 were prepared for loading iron nanoparticles (FeNPs), resulting in FeNPs@Co 3 O 4 hollow nanocages (FeNPs@Co 3 O 4 HNCs). FeNPs@Co 3 O 4 HNCs were characterized by SEM, TEM, XRD, XPS and FT-IR. The FeNPs@Co 3 O 4 HNCs composites could catalyze the oxidation of TMB into blue product by H 2 O 2 , showing better peroxidase-like activity than FeNPs and Co 3 O 4 HNCs. Notably, kinetic studies indicated that FeNPs@Co 3 O 4 HNCs behaved an excellent affinity to H 2 O 2 with K m value of 0.019 mM, which was 195 times lower than that of HRP. On this basis, a facile colorimetric biosensing method was established to detect glucose. The linear range was 0.5–30 μM, and the limit of detection was 0.05 μM. The proposed sensor was successfully used to determine glucose in human serum samples. The highly catalytic performance of FeNPs@Co 3 O 4 HNCs is attributed to its porous hollow structure, which is beneficial for dispersion of in situ formed FeNPs and for reducing the agglomeration. Further, the FeNPs@Co 3 O 4 HNCs catalysts with porous character provide an essential way to expose active sites as far as possible to the substrate and increase the catalytic active sites. [ABSTRACT FROM AUTHOR]

In this paper, we propose full discrete linear schemes for the molecular beam epitaxy (MBE) model with slope selection, which are shown to be unconditionally energy stable and unique solvable. In details, using the invariant energy quadratization (IEQ) approach, along with a regularized technique, the MBE model is first discretized in time using either Crank–Nicolson or Adam–Bashforth strategies. The semi-discrete schemes are shown to be energy stable and unique solvable. Then we further use Fourier-spectral methods to discretize the space, ending with full discrete schemes that are energy-stable and unique solvable. In particular, the full discrete schemes are linear such that only a linear algebra problem need to be solved at each time step. Through numerical tests, we have shown a proper choice of the regularization parameter provides better stability and accuracy, such that larger time step is feasible. Afterward, we present several numerical simulations to demonstrate the accuracy and efficiency of our newly proposed schemes. The linearizing and regularizing strategy used in this paper could be readily applied to solve a class of phase field models that are derived from energy variation. [ABSTRACT FROM AUTHOR]

Arpan Das et al. proposed a set of new Bell inequalities (Das et al., 2017 [16] ) for a three-qubit system and claimed that each inequality within this set is violated by all generalized Greenberger–Horne–Zeilinger (GGHZ) states. We investigate experimentally the new inequalities in the three-photon GGHZ class states. Since the inequalities are symmetric under the identical particles system, we chose one Bell-type inequality from the set arbitrarily. The experimental data well verified the theoretical prediction. Moreover, the experimental results show that the amount of violation of the new Bell inequality against locality realism increases monotonically following the increase of the tangle of the GGHZ state. The most profound physical essence revealed by the results is that the nonlocality of GGHZ state correlate with three tangles directly. [ABSTRACT FROM AUTHOR]

Purpose Lung cancer, the leading cause of cancer-related death worldwide, shows a poor 5-year overall survival rate. In our previous study, we demonstrated that miR-486-5p can be a potential blood-based biomarker for early diagnosis and recurrence prediction of non-small cell lung cancer (NSCLC). The aim of the present study was to investigate the possible roles and related target genes of miR-486-5p in NSCLC progression. Methods pcDNA3.1(+)/Pri-miR486 recombinant plasmid and miR-486-5p inhibitor were transfected into NSCLC cells and theirs effects were evaluated by qRT-PCR. Then, MTT assay and Colony formation assay were performed to determine the potential roles of miR-486-5p played on NSCLC cellular proliferation and cloning in vitro. We also initially investigated the target genes of miR-486-5p by using bioinformatic methods, qRT-PCR and western blot. Results pcDNA3.1(+)/Pri-miR486 recombinant plasmid significantly upregulated the expression of miR-486-5p , while miR-486-5p inhibitor significantly downregulated its expression. Upregulation of miR-486-5p promoted the cellular proliferation and cloning, while miR-486-5p silencing restrained the cellular proliferation and cloning. Furthermore, four potential target genes ( PIK3R1 , PTEN , MAP3K7 and FOXO1 ) of miR-486-5p were screened out. Finally, we found that upregulation of miR-486-5p in NSCLC cells significantly reduced PTEN and increased AKT expression levels, whereas miR-486-5p silencing increased PTEN and reduced AKT expression. Therefore, we believe that miR-486-5p can regulate PTEN-PI3 K/AKT signaling. Conclusions miR-486-5p acts as an oncogene in the progression of NSCLC by influencing PTEN-PI3 K/AKT signaling. miR-486-5p may provide potential therapeutic targets for NSCLC. [ABSTRACT FROM AUTHOR]

Bio-organic fertilizers (BOFs) combine functional microbes with a suitable substrate and have been shown to effectively suppress soil-borne diseases and promote plant growth. Here, we developed a novel bio-organic fertilizer (BOF) by fermentation of a cow plus chicken manure (M) compost using Fen-liquor Daqu (FLD) as a fermentation starter and compared the compositions of bacterial and fungal communities in the rhizosphere soil of watermelon plants after treatment with different fertilizers. Further, we aimed to explore the mechanisms underlying plant-promoting and disease (Fusarium wilt)-suppressing activities of each rhizosphere microbial community. The microbial communities of soil amended with cow plus chicken manure compost (S+M), soil amended with the BOF (S+BOF), and untreated control soil (S) without plants were analyzed through sequence analysis using the Illumina MiSeq platform. The results showed that a new microbial community was formed in the manure compost after fermentation by the Daqu. Application of the BOF to the soil induced remarkable changes in the rhizosphere microbial communities, with increased bacterial diversity and decreased fungal diversity. Most importantly, S+BOF showed the lowest abundance of Fusarium. Moreover, watermelon quality was higher (P < 0.05) in the S+BOF than in the S+M treatment. Thus, application of the BOF favorably altered the composition of the rhizosphere microbial community, suppressing Fusarium wilt disease and promoting plant quality. [ABSTRACT FROM AUTHOR]

As important part of components for 193 nm lithography, AlF 3 coatings deposited by resistive heating method acquire advantages like lower optical loss and higher laser damage threshold, but they also possess some disadvantages like worse stability, which is what aging effect focuses on. AlF 3 single-layer coatings were deposited; optical property, surface morphology and roughness, and composition were characterized in different periods. Owing to aging effect, refractive index and extinction coefficient increased; larger and larger roughness caused more and more scattering loss, which was in the same order with absorption at 193.4 nm and part of optical loss; from composition analysis, proportional substitution of AlF 3 by alumina may account for changes in refractive index as well as absorption. [ABSTRACT FROM AUTHOR]

The data are rapidly expanding nowadays, which makes it very difficult to analyze valuable information from big data. Most of the existing data mining algorithms deal with big data problems at large time and space costs. This paper focuses on the sampling problem of big data and puts forward an efficient heuristic Cluster Sampling Arithmetic, called CSA. Many of the former researchers adopted random method to extract early sample set from the original data and then made a variety of different processing of the sample in order to obtain the corresponding minimum sample set, which is regarded as a representation of the original big data set. However, the final processing results of big data will be severely affected by the random sampling process at the beginning, resulting in lower comprehensiveness and quality of the final data results and longer processing time. Based on this view, CSA introduces the idea of clustering to obtain minimum sample set of big data, which is in contrast to the random sampling method in the current literature. CSA makes cluster analysis of the original data set and selects the center of each class as centralized members of the minimum sample set. It aims at ensuring that the sample distribution accords with the characteristics of the original data, guarantees the data integrity and reduces the processing time. The max-min distance means that the pattern recognition has been integrated into the clustering process in order to get the clustering center and prevent algorithm from local optimum. The final experimental results show that, compared with the existing work, CSA algorithm can efficiently reflect the characteristics of the original data and reduce the time of data processing. The obtained minimum sample set has also achieved good effects in the classification algorithm. [ABSTRACT FROM AUTHOR]

Complex motions of targets cause migration through resolution cells which leads to the inverse synthetic aperture radar (ISAR) image blurred and makes difficulties to follow-up work such as identification, recognition, and classification. In this paper, a novel ISAR imaging algorithm based on the fractional tap length keystone transform (FTLKT) is proposed for multiple targets with complex motions. In noncooperation case, different targets behave variously. For phase coupling of different orders, the proposed algorithm first employs FTLKT to achieve decoupling of the frequency and slow time variable, then detection of Doppler peaks is applied for ambiguity resolution of different targets. According to this, focused ISAR images of different targets are obtained. Simulation results demonstrate the validity of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In the challenging α,β-unsaturated aldehydes and ketones hydrogenation to unsaturated alcohols (UA), Ru-Au/MCM-41 exhibits superior high activity and selectivity compared with monometallic Ru. TEM and XRD measurements were applied to characterize as-prepared Ru/MCM-41 and Ru-Au/MCM-41 catalysts. The results indicated that the addition of Au significantly improved the dispersion of the metallic Ru components, thus enhancing the activity of the catalyst. The enhancement of selectivity to UA could be attributed to the interaction of Ru and Au components in the support and the morphology effect of Ru, which are revealed by in-suit DRIFTS, H-TPD, XPS, and FTIR measurements. The morphological and electronic aspects of Ru particles lead to a favorable adsorption of C=O bond versus C=C bond. A dramatic increase in activity and selectivity of the reactions were observed upon the addition of Au, suggesting that the significant synergistic effects between Ru and Au play an important role in the activity and selectivity of the reaction. It is the first time that chemoselective hydrogenation of α,β-unsaturated aldehydes and ketones were studied on Ru-Au/MCM-41 catalysts. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Inverse synthetic aperture radar (ISAR) imaging is an efficient method for providing high resolution image of maneuvering target especially in many military applications. Practically, the received echoes of complex maneuvering target are always described as cubic phase signals (CPS). Then, migrations through resolution cells are inevitably induced. Additionally, for scenes in which multiple targets exist, the situations become even worse. In this paper, an algorithm for parameters estimation and ISAR imaging of multiple maneuvering targets is proposed, where adjacent cross correlation function (ACCF), modified keystone transform (MKT), fractional Fourier transform (FrFT) and Hough transform (HT) are employed. The algorithm firstly employs ACCF to obtain a reduced order of the original CPS. Then, MKT and FrFT are introduced to realize parameters estimation of multiple targets. Thirdly, motion compensations for each target are accomplished with the estimators. Noting that the radar echoes are not separated previously, compensation result for one target is certainly interfered by the signal components of the others. To resolve this problem, edge detection and HT are utilized to separate the corrected range profile history. Finally, focused ISAR images of each target are obtained after azimuth compression. Simulation results demonstrate the validity of the proposed algorithm. [ABSTRACT FROM PUBLISHER]

Mobile cloud computing has become a research hotspot in the fields of cloud computing and mobile computing. At present, many researches on offloading computation to cloud resource and their related work have been done and some achievements have been obtained in the field of mobile cloud computing. However, some problems of the current researches have also been found such as the separation between computation and data, limited network resource, and lack of location-aware, etc. In this paper, we have presented a novel mobile cloud computing model and proposed a heuristic approach MCC-particle swarm optimization (PSO) of placement selection of mobile applications' partitions for minimizing the overall processing time and energy saving. The algorithm of the proposed MCC-PSO approach includes two parts. One is that it combines the PSO idea with the simulated annealing (SA) idea to achieve an improved PSO-based approach with the better global search's ability. The other one is that it uses the probability theory and mathematical statistics and once again utilizes the SA idea to deal with the data obtained from the improved PSO-based process to get the final solution. And thus the whole approach achieves a long-term optimization of mobile cloud computing. The experimental results demonstrate that MCC-PSO evidently reduces the overall processing time of mobile applications and energy consumption of mobile devices while better guaranteeing the performance of executing mobile applications. MCC-PSO better achieves the idea of mobile cloud computing and makes the mobile cloud computing model more high-effective and meaningful. [ABSTRACT FROM AUTHOR]

A doubly Q-switched Nd:GGG laser emitting 1064 nm wavelength with an acousto-optic modulator (AOM) and a monolayer graphene saturable absorber (SA) is presented to study the pulse characteristics. In comparison with singly passive Q-switched laser (SPQSL) with grapheme SA, the doubly Q-switched laser (DQSL) can effectively shorten the pulse width and improve the pulse peak power. The existence of the ramping behavior of pulse characteristics versus modulation frequency in DQSL is shown. The average output power, the pulse width, the pulse energy and the peak power are related to modulation frequency of AOM, and the point of inflection is dominated by pump power. [ABSTRACT FROM AUTHOR]

A doubly Q-switched Nd:GGG laser emitting 1064 nm wavelength with an acousto-optic modulator (AOM) and a few-layer MoS 2 saturable absorber (SA) is presented to study the pulsed laser characteristics. The average output power, the pulse width, the pulse energy and the peak power versus pump power for different modulation frequency of AOM are measured. In comparison with singly passive Q-switched laser (SPQSL) with MoS 2 SA, the doubly Q-switched laser (DQSL) can effectively shorten the pulse width, improve the pulse peak power and the stability. The shortest pulse width is 150.1 ns and the maximum peak power reaches 33.7 W. The maximum pulse compression ratio 5.8 and the highest peak power enhancement factor 21.3 are obtained, respectively. [ABSTRACT FROM AUTHOR]

How to develop efficient numerical schemes while preserving energy stability at the discrete level is challenging for the three-component Cahn-Hilliard phase-field model. In this paper, we develop a set of first- and second-order temporal approximation schemes based on a novel 'Invariant Energy Quadratization' approach, where all nonlinear terms are treated semi-explicitly. Consequently, the resulting numerical schemes lead to well-posed linear systems with a linear symmetric, positive definite at each time step. We prove that the developed schemes are unconditionally energy stable and present various 2D and 3D numerical simulations to demonstrate the stability and the accuracy of the schemes. [ABSTRACT FROM AUTHOR]

A facile and practical [3+2] cycloaddition/ring contraction for the construction of structurally diverse CF 2 H-containing spirocyclopropyloxindoles was developed. Starting from isatin-derived 3-ylideneoxindoles and in situ generated CF 2 HCHN 2 , the desired products were obtained in good to excellent results (up to 99% yield and >99:1 trans/cis ) in the absence of metal catalyst. The potential application of the protocol was also demonstrated by the synthesis of the CF 2 H-substituted analog of HIV-1 NNRTI inhibitor. [ABSTRACT FROM AUTHOR]

Nanoporous Co-doped Zn1−xCdxS were facilely fabricated via adopting ZIFs as templates, and Cd(NO3)2 and thiourea as precursors. The highly porous microstructure and uniform Co-doping of the photocatalyst afford a high H2-production rate (45.2 and 422.2 times larger than those of Zn0.5Cd0.5S and CdS), providing an effective way for the development of high performance nanoporous photocatalysts. [ABSTRACT FROM AUTHOR]