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The compression behavior of the lattice-walled tubes under variable strain rates are investigated by numerical simulation, and the stress-strain relationship of the structure under quasi-static loading is theoretically analyzed. The finite element software LS-DYNA is used to simulate the structure established by the beam element, and the critical impact velocity is obtained when the structure collapses layer by layer. According to the plastic hinge theory and considering the combined action of the beam's bending moment and axial force in the structure, the stress-strain relationship of the structure under quasi-static loading is derived and compared with the experimental results. The numerical simulation results reveal that the structure of the single-layer gradient tube(SGC) does not undergo shear deformation under quasi-static and low-speed impact. The critical speed of the gradient square tube(GS) is higher than that of a cylindrical tube. The theoretical model can correctly reflect the mechanical response of the structure under uniaxial compression.

Inverse design has long been an efficient and powerful design tool in the aircraft industry. In this paper, a novel inverse design method for supercritical airfoils is proposed based on generative models in deep learning. A Conditional Variational AutoEncoder (CVAE) and an integrated generative network CVAE-GAN that combines the CVAE with the Wasserstein Generative Adversarial Networks (WGAN), are conducted as generative models. They are used to generate target wall Mach distributions for the inverse design that matches specified features, such as locations of suction peak, shock and aft loading. Qualitative and quantitative results show that both adopted generative models can generate diverse and realistic wall Mach number distributions satisfying the given features. The CVAE-GAN model outperforms the CVAE model and achieves better reconstruction accuracies for all the samples in the dataset. Furthermore, a deep neural network for nonlinear mapping is adopted to obtain the airfoil shape corresponding to the target wall Mach number distribution. The performances of the designed deep neural network are fully demonstrated and a smoothness measurement is proposed to quantify small oscillations in the airfoil surface, proving the authenticity and accuracy of the generated airfoil shapes.

A Ag@CuFe2O4@TiO2 nanocomposite film with high performance of photogenerated cathodic protection was prepared by hydrothermal and photoreduction methods. The results showed that when the CuFe2O4 hydrothermal reaction time was 6 h and the AgNO3 concentration was 0.1 M, the Ag@CuFe2O4@TiO2 nanocomposite material performed the best cathodic protection capability for 304 stainless steel (304SS). In this case, the protective potential achieved −930 mV (versus SCE) associated with the photocurrent density of 475 μA/cm2, which was 14.8 times that of pure TiO2 nanowires. In the dark, the nanocomposite provided cathodic protection of up to 485 mV for 304SS. Due to the heterogeneous junctions at the two interfaces among the three kinds of nanocomposite materials, the build-in electric field was fabricated, which promoted the separation efficiency of photogenerated electrons and holes and effectively improved the photochemical cathodic protection of 304SS.

Hexagonal boron nitride (h-BN) fillers are incorporated into poly(vinyl butyral) (PVB) coatings to improve the corrosion protection performance of copper. It has been revealed that the h-BN fillers exhibit an excellent dispersiblility in PVB coating due to the non-covalent interactions between h-BN fillers and the PVB molecules. Electrochemical characterization reveals that the corrosion resistance of the BN-reinforced PVB (BN-P) coating is 5–6 orders of magnitude higher than that of the pristine PVB coating. Photographs and metallography show that the copper substrate beneath the BN-P coating does not suffer from corrosion after immersion for 2 months, indicating that the BN-P coating can provide a long-term protective barrier for the underlying copper substrate. Loading 0~0.25 g h-BN fillers in 2.0 g PVB, the corrosion protection performance increases with increasing the loading of h-BN fillers. The scratch test results suggest that h-BN fillers do not accelerate copper corrosion when the BN-P coating is damaged.

Sr2MgWO6 (SMW) is a typical perovskite oxide compound, but there has been little research on the effects of processing on its dielectric properties. In this work, SMW ceramics were prepared by solid-state synthesis with sintering at 1450 °C, 1475 °C, 1500 °C and 1525 °C, respectively. XRD results confirmed that the samples possessed double perovskite structure (Fm-3m). The Raman and FTIR spectra were used to study the lattice vibrational modes. The FPSQ model was used to obtain the fitting curves of the FTIR spectra and derive the intrinsic properties of the material that were found to be in agreement with the measured data. The structure-property relationships were successfully established based on the Raman mode results. The optimal sintering temperature of SMW ceramics was identified as 1475 °C due to the excellent performances characteristics (er = 16.97, Q × f = 23,872 GHz, τf = −35.38 ppm/°C) obtained at this temperature. This study explored the relationships among the crystal structures, lattice vibrational characteristics and dielectric properties of SMW ceramics, so as to further understand their dielectric response mechanism and lay a solid theoretical foundation for the development of microwave ceramics.

Temperature gradient significantly affects the production of surrounding rock stress in mining engineering. The mechanics and deformation characteristics of the rock will change under the temperature gradient, thereby increasing the probability of accidents in the roadway. This paper conducts uniaxial compression tests on granite at different temperatures from room temperature to 250∘C, and analyzes in detail the changes in the stress-strain curve, peak stress, peak strain and tangent modulus of granite under high temperature and different temperature gradient conditions. The results of this study are as follows: (1) Under high temperature conditions, the granite’s peak stress and tangent elastic modulus increased with temperature from 17 to 100∘C, then decreased from 100∘C to 250∘C, whereas the granite’s peak strain increased steadily with increasing temperature; (2) under temperature gradient, the granite’s peak stress and tangent modulus first decreased and then increased with increasing temperature gradient, while the granite’s peak strain first decreased and then increased at 100∘C, but first increased and then decreased from 150∘C to 250∘C.

Here we report a fossil flora from the Miocene Toupi Formation in Jiangxi Province, southeastern China, including megafossil genera Pinus, Podocarpus, Calocedrus, Cinnamomum, Quercus, Lithocarpus, Carya, Palaeocarya, Acer, and Yua. Among them, Yua jiangxiensis n. sp. is the first fossil record of the genus in Asia. A palynological analysis in this study reveals that the palyno-assemblage contains Selaginella, Pteris, Pinus, Picea, Quercus, Fagus, Carya, Ilex, and Rutaceae. Based on Integrated Plant Records (IPR) vegetation analysis, it is suggested that the fossil flora represents an evergreen broad-leaved forest, and the occurrence of tropical and subtropical Cinnamomum supports a warm and moist climate in the region during the middle Miocene.

A nuclear-encoded sigma (σ) factor is essential for the transcriptional regulation of plant chloroplast-encoded genes. Five putative maize σ factors have been identified by database searches, but their functions are unknown. We report a maize leaf color mutant etiolated/albino leaf 1 (eal1) that was derived from space mutation breeding. The eal1 mutant displays etiolated or albino leaves that then gradually turn to normal green at the seedling stage. The changes in eal1 leaf color are associated with changes in photosynthetic pigment content and chloroplast development. Map-based cloning revealed that a single amino-acid deletion changing Val480-Val481-Val482 to Val480-Val481, in the C-terminal domain σ4 of the putative σ factor ZmSig2A, is responsible for the eal1 mutation. In comparison with the expression level of the wild-type (WT) allele ZmSig2A+ in WT plants, much higher expression of the mutant allele ZmSig2AΔV in eal1 plants was detected before the eal1 plants turned to normal green. ZmSig2A shows the highest similarity to rice OsSig2A and Arabidopsis SIG2. Ectopic expression of ZmSig2A+ or ZmSig2AΔV driven by the cauliflower mosaic virus 35S promoter rescued the pale green leaf of the sig2 mutant, but ectopic expression of ZmSig2AΔV driven by the SIG2 promoter did not. We propose that the Val deletion generated a new weak allele of ZmSig2A that cannot completely abolish the ZmSig2A function. Some genes involved in chloroplast development and photosynthesis-associated nuclear genes showed significant expression differences between eal1 and WT plants. We conclude that ZmSig2A encoding a σ factor is essential for maize chloroplast development. The eal1 mutant with a weak allele of ZmSig2A represents a valuable genetic resource for investigating the regulation of ZmSig2A-mediated chloroplast development in maize. The eal1 mutation may be useful as a marker for early identification and elimination of false hybrids or transgene transmission in the application of genetic male sterility to commercial hybrid seed production.

Graphene films (GFs) and graphene-reinforced nanocomposite coatings (GNCs) have received unprecedented attention for corrosion protection because graphene possesses a remarkable chemical inertness and is completely impermeable to aggressive chemicals. However, the high electric conductivity and positive potential of graphene make graphene-based metal protectors tend to exhibit an undesirable high corrosion-promotion activity (CPA), which is widely known as the phenomenon that graphene connecting with metal accelerates the corrosion of metal substrate by inducing micro-galvanic corrosion at the defect sites of GFs or GNCs in aggressive environments. Therefore, inhibiting the CPA of graphene is currently a key focus for the application of graphene in the field of corrosion protection. In this review, the mechanisms, influencing factors, and inhibition strategies of the CPA of GFs and GNCs are highlighted from the point of view of corrosion science to address the bottlenecks and challenges for future research and potential applications of graphene for corrosion protection.

Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications, which are becoming increasingly important for power electronics nowadays. Among them, AgNbO3 based lead-free ceramics have attracted intensive interest as one of promising environmental-friendly candidates. However, most of the AgNbO3 based ceramics suffers from low dielectric breakdown strength (Eb). The limitation of low Eb is broken to some extent in this work. Here, AgNbO3 epitaxial films were fabricated by pulsed laser deposition, which possess high Eb of 624 kV/cm. The (001)AgNbO3 epitaxial film reveals typical antiferroelectric hysteresis loops when the applied electric fields are over 300 kV/cm. A recoverable energy density of 5.8 J/cm3 and an energy efficiency of 55.8% are obtained at 600 kV/cm, which demonstrates the great promise of the AgNbO3 film for energy storage applications.

In this study, a trifunctional strategy was developed to prepare a confined Ni-based catalyst (Ni-CeO2@SiO2) for dry reforming of methane (DRM) of two main greenhouse gases—CO2 and CH4. The Ni-CeO2@SiO2 catalyst was fabricated by utilizing the confinement effect of the SiO2 shell and the synergistic interaction between Ni-Ce and the decoking effect of CeO2. The catalysts were systematically characterized via X-ray diffraction, N2 adsorption/desorption, transmission electron microscopy, energy dispersive X-ray spectroscopy, hydrogen temperature reduction and desorption set by program, oxygen temperature program desorption, Raman spectroscopy, thermogravimetric analysis, and in situ diffuse reflectance infrared Fourier transform spectroscopy measurements to reveal their physicochemical properties and reaction mechanism. The Ni-CeO2@SiO2 catalyst exhibited higher activity and stability than the catalyst synthesized via the traditional impregnation method. In addition, no carbon deposition was detected over Ni-CeO2@SiO2 after a 100 h durability test at 800 °C, and the average particle size of Ni nanoparticles (NPs) in the catalyst increased from 5.01 to 5.77 nm. Remarkably, Ni-CeO2@SiO2 also exhibited superior low-temperature stability; no coke deposition was observed when the catalyst was reacted at 600 °C for 20 h. The high coking and sintering resistance of this confined Ni-based DRM catalyst can be attributed to its trifunctional effect. The trifunctional strategy developed in this study could be used as a guideline to design other high-performance catalysts for CO2 and CH4 dry forming and accelerate their industrialization.

Cordierite glass-ceramics usually begin to crystallize from the surface. As an efficient nucleating agent, TiO2 can promote the rapid transformation of glass to bulk crystallization, but it is easy to cause the increase of dielectric constant and light absorption. High crystallinity cordierite glass-ceramics were prepared by optimizing the heat treatment process without or with different nucleating agents in stoichiometric cordierite glasses. The results show that the crystallization mechanisms of glasses without and with ZrO2+P2O5 as nucleation agents are controlled by surface crystallization. While, the glass with TiO2+ZrO2+P2O5 as nucleation agents have the tendency to be bulk crystallization. The studied glasses are crystallized from surface and have different crystallization orientations with the inner glass. The thickness of crystalline layer increased with the increasing of heating temperatures, but the “surface-center” crystallization process cannot complete by further increasing heating temperatures because of softening deformation of glasses. At 1020 ℃, the glasses complete the “surface-center” crystallization for long durations. The glasses without nucleation agents and with ZrO2+P2O5 require 10 h, but the glass with TiO2+ZrO2+P2O5 complete for 5 h. Although all the three glasses complete the “surface-center” crystallization, the glasses with nucleation agents show the higher crystallinity upon the same heat treatments. Finally, glass-ceramics with excellent performance were obtained, for example, the Z1# glass-ceramic have the high microhardness ∼7.4 GPa, low thermal expansion coefficient ∼1.4☓10−6 ℃−1 at 20–300 ℃, and relatively high thermal conductivity ∼2.4 W/mK. It also exhibits low dielectric constant and loss, which was ∼4.5 and ∼1.2☓10−3 at 1 MHz, ∼ 4.9 and 2.3☓10−3 at 10.5 GHz..

It is still a big challenge to calculate the probability of defect detection for inspecting pits on austenitic stainless steel welding using traditional POD models. Because we determine the decision threshold, the POD curve has a lot of changes as the decision threshold changes, there is no clear reason to insist which threshold is reasonable. This study proposes a new probability of detection (POD) model to quantitatively assess the detection capability of eddy current probes for inspecting pits on austenitic stainless steel welding. The experimental results show that the proposed model is more reasonable than traditional ones. The novel POD model was employed to analyze three eddy current probes, uniform, TR, plus-point probes on austenitic stainless steel welding. The results reveal that the uniform eddy current probe has the best detection capability for inspecting pits on among the three probes.

In light of the intriguing potential of anti-angiogenic approach in suppressing choroidal neovascularization, we attempted to elaborate synthetic gene delivery systems encapsulating anti-angiogenic plasmid DNA as alternatives of clinical antibody-based therapeutics. Herein, block copolymer of cyclic Arg-Gly-Asp-poly(ethylene glycol)-poly(lysine-thiol) [RGD-PEG-PLys(thiol)] with multifunctional components was tailored in manufacture of core-shell DNA delivery nanoparticulates. Note that the polycationic PLys segments were electrostatically complexed with anionic plasmid DNA into nanoscaled core, and the tethered biocompatible PEG segments presented as the spatial shell (minimizing non-specific reactions in biological milieu). Furthermore, the aforementioned self-assembly was introduced with redox-responsive disulfide crosslinking due to the thiol coupling. Hence, reversible stabilities, namely stable in extracellular milieu but susceptible to disassemble for liberation of the DNA payloads in intracellular reducing microenvironment, were verified to facilitate transcellular gene transportation. In addition, RGD was installed onto the surface of the proposed self-assemblies with aim of targeted accumulation and internalization into angiogenic endothelial cells given that RGD receptors were specifically overexpressed on their cytomembrane surface. The proposed anti-angiogenic DNA therapeutics were validated to exert efficient expression of anti-angiogenic proteins in endothelial cells and elicit potent inhibition of ocular neovasculature post intravitreous administration. Hence, the present study approved the potential of gene therapy in treatment of choroidal neovascularization. In light of sustainable gene expression properties of DNA therapeutics, our proposed synthetic gene delivery system inspired prosperous potentials in long-term treatment of choroidal neovascularization, which should be emphasized to develop further towards clinical translations., Graphical abstract Image, graphical abstract

Fungal dimorphism is the ability of certain fungi to switch between two different cellular forms, yeast and mycelial forms, in response to external environmental factors. The pacC/Pal signal transduction pathway responds to neutral and alkaline environments and is also involved in the fungal dimorphic transition. In this study, we investigated the function of the pacC homolog, MripacC, which regulates the dimorphic transition and modulates virulence of the insect pathogenic fungus Metarhizium rileyi. MripacC expression was upregulated under alkaline condition, with increased number of yeast-like cells compared to the number of hyphae cells. A MripacC deletion mutant (ΔMripacC) was obtained by homologous replacement and exhibited decreased blastospore budding, with direct development of conidia into hyphae without entering the yeast-like stage when cultured on alkaline medium. Observation of host hemolymph morphology and analysis of samples to detect the main immune factors revealed a decreased ability of ΔMripacC to evade the host immune system. The results of insect bioassays showed that ΔMripacC had decreased virulence with extended median lethality time. Together, the results suggested that MripacC not only regulated adaptation to acidic and alkaline environments, but also influenced virulence by budding blastospores. This elucidation of the function of MripacC adds to our understanding of blastospore budding and virulence of this fungal pathogen.

Crystallization of glass has significant effects on glass structure and the resultant ion-exchange behaviors. In this work, transparent glass-ceramics (GCs) with sequential crystallization of ZnAl2O4 and β-quartz solid solution nanocrystals (NCs) were prepared, and effects of the crystallization on microstructure and ion-exchange properties were investigated. Compared with the specimen with simultaneous precipitation of ZnAl2O4 and β-quartz solid solution NCs, GCs with sequential crystallization of ZnAl2O4 and β-quartz solid solution NCs show smaller grain size and more uniform structure and higher transparency. Ion-exchange depth of layer (DOL) increases significantly with the crystallization of the specimens due to the reduction in content of zinc and five coordinated aluminum in the residual glass matrix. High residual compressive stress and Vickers hardness can be obtained after ion-exchange in KNO3 molten salt.

When kinematic control of robot manipulator is modeled as time-varying problems, control algorithms generated by solving time-varying problems perform well in the aspect of real-time control and control precision. However, conventional algorithms are based on relatively simple time-varying problems modeling and solving, and thus, it is difficult for them to solve more other problems while completing tracking task. In this work, the kinematic control of robot manipulator is first modeled as more complicated multilayered time-varying problem, which simultaneously formulates the tracking task and joint angle limits. Then, zeroing neural dynamics method is future investigated to find the equivalence of multilayers. Finally, three explicit solutions based on three discretization formulas are presented to solve the multilayered time-varying problem. The presented solutions not only complete the tracking task in real time with different precision, but also solve the problem of joint angle limits during the control process.

This work analyzes and discusses the influence of human activities on the meteorological conditions related to winter haze events in Beijing, Tianjin, and Hebei (i.e., the Jing–Jin–Ji region) during 1961–2016, using the results of two numerical simulation experiments based on the Community Atmosphere Model version 5.1.1 (http://www.cesm.ucar.edu/models/cesm1.0/cam/docs/ug5_1_1/book1.html) used in the international Climate Variability and Predictability Programme (CLIVAR) Climate of the 20th Century. Detection and Attribution Project (C20C+ D&A). The results show that, under the influence of human activities, the changes in dynamical and thermal meteorological conditions related to winter haze events in the Jing–Jin–Ji region are conducive to the formation and accumulation of haze, and prevent the diffusion of pollutants. The dynamical conditions mainly include the obvious weakening of the East Asian winter monsoon (EAWM) and the enhancement of the near-surface anomalous southerly wind. The thermal conditions include the obvious increase in surface temperature, and the enhancement of water vapor transport and near-surface inversion. The relative contribution of dynamical and thermal conditions to the variation of haze days in the Jing–Jin–Ji region is analyzed using statistical methods. The results show that the contribution of human activities to the increase of haze days in the Jing–Jin–Ji region is greater than that of natural forcing for the study period. To be specific, the dynamical meteorological factors contribute more to the haze days than the thermal meteorological factors. The contribution of thermal meteorological factors is basically the same in both scenarios.

This article has been retracted, and the online PDF has been watermarked “RETRACTION”. The retraction notice is available at http://doi.org/10.3233/MGC-220950.

This article investigates the dynamics of a mixed triopoly game in which a state-owned public firm competes against two private firms. In this game, the public firm and private firms are considered to be boundedly rational and naive, respectively. Based on both quantity and price competition, the game’s equilibrium points are calculated, and then the local stability of boundary points and the Nash equilibrium points is analyzed. Numerical simulations are presented to display the dynamic behaviors including bifurcation diagrams, maximal Lyapunov exponent, and sensitive dependence on initial conditions. The chaotic behavior of the two models has been stabilized on the Nash equilibrium point by using the delay feedback control method. The thresholds under price and quantity competition are also compared.

Recent progress in using real-time kinematic (RTK) positioning has motivated the exploration of its application due to its high accuracy and efficiency. However, poorly-observed satellite data will cause unfixed ambiguities and markedly biased solutions. A novel partial ambiguity resolution method, named the irrespective of integer ambiguity resolution (IIAR) model, is proposed and applied to improve the reliability of ambiguity resolution. The proposed method contains initial ambiguity resolution and irrespective of integer ambiguity processes. The initial ambiguity resolution process applies an iterative partial ambiguity resolution method to obtain an approximate solution. The irrespective of integer ambiguity process transforms the approximate solution to a high-precision solution. Experiments show that the approximate solution is unreliable when the initial ambiguity resolution process has small redundancy, and the proposed method can obtain better results for those cases. The IIAR method showed about a 40% improvement of multi-GNSS ambiguity success rate and about a 25% improvement of standard deviation. Therefore, these results show that the proposed IIAR method can improve the results of multi-GNSS RTK positioning significantly.

Ni-rich cathode materials show great potential of applying in high-energy lithium ion batteries, but their inferior cycling stability hinders this process. Study on the electrode/electrolyte interfacial reaction is indispensable to understand the capacity failure mechanism of Ni-rich cathode materials and further address this issue. This work demonstrates the domain size effects on interfacial side reactions firstly, and further analyzes the inherent mechanism of side reaction induced capacity decay through comparing the interfacial behaviors before and after MgO coating. It has been determined that LiF deposition caused thicker SEI films may not increase the surface film resistance, while HF erosion induced surface phase transition will increase the charge transfer resistance, and the later plays the dominant factor to declined capacity of Ni-rich cathode materials. This work suggests strategies to suppress the capacity decay of layered cathode materials and provides a guidance for the domain size control to match the various applications under different current rates.

As the population ages, more and more people are suffering from osteoarthritis (OA), resulting in an increasing requirement for joint implants. Surface modification to improve the topology and composition of the implants has been proved to be an effective way to improve the primary stability and long-term success rate of joint implants. In this work, a bionic micro/nano-structure accompanied with a strontium-substituted hydroxyapatite (SrHA) coating was fabricated on titanium (Ti) surface via electrochemical corrosion, ultrasonic treatment, and hydrothermal deposition methods. The in vitro study demonstrated that the bionic structure and the bioactive apatite could synergistically increase the expressions of integrin-related gene (ITG α5β1) and osteoblastic genes (Col-I and OCN), and thus promote osteoblast growth. In addition, owing to the anti-bone resorption property of Sr2+, the coating could effectively inhibit osteoclast differentiation and proliferation. In a word, the prepared samples not only promoted osteogenesis but also inhibited osteoclastogenesis. The in vivo experiment via a rabbit model found that the bionic structured surface provided the pore for new bone ingrowth, which was beneficial to the mechanical interlocking between the implant and bone. Moreover, the bionic structure and bioactive SrHA coating had a synergistic effect on promoting bone formation, osseointegration, and bone-implant bonding strength. This study therefore presented a new strategy to fabricate bio-functionalized Ti-based implants for potential application in orthopedics field.

Epsilon toxin (ETX) is a key pathogenic factor of C. perfringens type B and D, causing fatal enterotoxemia in sheep and goats. Excessive production of ETX increases intestinal permeability; its entrance into the bloodstream leads to severe edema in organs such as the brain and kidneys. At present, very few cell lines are known to be sensitive to ETX, with the most sensitive cell model for in vitro research being the MDCK cell line. Recently, more tissue-derived cell lines have been shown to be sensitive to ETX, but the mechanism of cytotoxicity remains unknown. Herein, for the first time, we aimed to evaluate the effects of ETX on HaCaT keratinocytes and human epidermal keratinocytes (HEKa). In addition, the median lethal dose of subcutaneous injection of ETX in mice was 109 ng/kg. At this dose, ETX rapidly entered the blood circulation, causing hemorrhage and edema in the brain and kidneys. ETX also increased the expression of aquaporin 3 in the muscle layer and hair follicles of the skin. We further showed the presence of the MAL protein in HaCaT keratinocytes and HEKa and skin tissues, supporting the hypothesis that it is a key element in the mechanism of cytotoxicity of ETX. In conclusion, skin cell lines were used for the first time as a model for studying the toxic effects of ETX, which will help elucidate the cytotoxicity induced by ETX and the related molecular mechanisms.

In this paper, we show that a simple generalization of the holographic axion model can realize spontaneous breaking of translational symmetry by considering a special gauge-axion higher derivative term. The finite real part and imaginary part of the stress tensor imply that the dual boundary system is a viscoelastic solid. By calculating quasi-normal modes and making a comparison with predictions from the elasticity theory, we verify the existence of phonons and pseudo-phonons, where the latter is realized by introducing a weak explicit breaking of translational symmetry, in the transverse channel. Finally, we discuss how the phonon dynamics affects the charge transport., v3: 29 pages, 11 figures, matching the version published in JHEP

First evidence of a structure in the $J/\psi{\Lambda}$ invariant mass distribution is obtained from an amplitude analysis of$\Xi_b^-{\rightarrow}J/\psi{\Lambda}K^-$ decays. The observed structure is consistent with being due to a charmonium pentaquark with strangeness with a significance of $3.1\sigma$ including systematic uncertainties and look-elsewhere effect. Its mass and width are determined to be $4458.8\pm2.9^{+4.7}_{-1.1}$ MeV and $17.3\pm6.5^{+8.0}_{-5.7}$ MeV, respectively, where the quoted uncertainties are statistical and systematic. The structure is also consistent with being due to two resonances. In addition, the narrow excited $\Xi^-$ states, $\Xi(1690)^-$ and $\Xi(1820)^-$, are seen for the first time in a $\Xi^-_b$ decay, and their masses and widths are measured with improved precision. The analysis is performed using $pp$ collision data corresponding to a total integrated luminosity of 9 fb$^{-1}$, collected with the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV.

Background The γ-glutamyl peptides refer to a series of bioactive peptides containing γ-glutamyl residues. The unique γ-glutamyl linkage endows γ-glutamyl peptides with higher in vivo stability and longer half-life, which contributes to their potent physiological functions. Recently, γ-glutamyl peptides have become the focus of researchers due to the unique Kokumi taste and various potential bioactivities mediated through activation of the calcium-sensing receptor (CaSR). However, review articles on the emerging bioactivities and potential mechanisms responsible for intestinal absorption of γ-glutamyl peptides are very scanty. Scope and approach This article aimed to discuss the significance and role of γ-glutamyl peptides in human health. The present review systematically summarizes the available scientific information on the preparation, CaSR, bioactivity and bioavailability of food-derived γ-glutamyl peptides. Furthermore, the current scientific challenges and future research directions are also discussed. Key findings and conclusions γ-Glutamyl peptides have been reported to exhibit diverse bioactivities, including anti-inflammatory, hypoglycemic and appetite-suppressing effects as well as the ameliorating effect on colon health, which are attributed to CaSR activation. Moreover, due to the high resistance towards gastrointestinal digestion, γ-glutamyl peptides can play a key role in the gastrointestinal tract and also be transported across the intestinal epithelium mainly via peptide transporter 1 (PepT1) or paracellular routes to exhibit various in vivo activities. In addition, further and intensive investigations are urgently required to address the current challenges pertaining to the effective preparation, novel physiological functions and exact absorption mechanisms of γ-glutamyl peptides. This review contributes to a better understanding of γ-glutamyl peptides in terms of their cellular receptor, bioactivity and bioavailability.

Hypocotyl phototropism is redundantly mediated by phot1 and phot2, two blue light receptor phototropins, under the intensity of blue light>1 μmol m−2 s−1. As light intensity increases, phot1 inhibits the phot2-mediated response. To date, only Arabidopsis Root Phototropism2 (RPT2) has been shown to participate in phot1-mediated inhibition of phototropism. To dissect the signaling network that underlies phot1-mediated inhibition, we carried out a yeast two-hybrid (Y2H) screening assay for RPT2 interacting proteins and identified J-domain protein required for chloroplast accumulation response 1 (JAC1). The interaction between JAC1 and RPT2 was verified by bimolecular fluorescence complementation and Co-IP assays. JAC1 is expressed mainly in cotyledons and hypocotyls. Like RPT2, JAC1 can be induced by blue light, suggesting that it may function similarly to RPT2 in the inhibition of phototropism. Genetic analysis showed that jac1 mutation significantly enhanced the hypocotyl bending of phot1 mutants towards intermediate-intensity blue light, and this effect was inhibited by the constitutive expression of JAC1 in the phot1 jac1 mutant. The phot1 rpt2 double mutant also exhibited enhanced phototropism compared with the phot1 mutant. Taken together, our data clearly demonstrate that JAC1 cooperates with RPT2 to negatively regulate hypocotyl phototropism in plants and may act either downstream of or in parallel with phot1.

In this paper, we investigate an interesting commuting problem for an electric vehicle (EV) corridor in a dense city where en-route charging (including home- and workplace-charging) services are provided, and apply the proposed EV corridor model for charging location optimization and traffic management. Along a transport corridor in a dense city, EV commuters can choose either road paths (with/without en-route charging) or transit path to complete their home-to-workplace travel journeys. We first propose a user equilibrium model for the commuting problem in the EV corridor, by taking into account both departure time and travel path choices. Departure time equilibriums for bottleneck-constrained road paths with and without en-route charging are respectively derived. We also give a condition that ensures all EV users arrive early at the destination for the path with road and charging bottlenecks (serial bottlenecks), and discuss the existence and uniqueness of the user equilibrium solution. Based on the proposed EV corridor model, we further develop a joint optimization model of charging location and road capacity allocation, for two bottleneck-constrained road paths, to manage traffic flows. Numerical experiments are carried out to interpret the EV-corridor commute equilibrium and to validate the joint traffic management strategy in enhancing the travel efficiency of the EV corridor.

Poor thermal conductivity, especially in thickness direction, is a major obstacle to extend the service lifetime of C/SiC composite. However, there are few papers focusing on finely designing heat conductive channel but a simply introduction of various modifiers to improve C/SiC thermal conductivity, which leads to less success. Herein, multi-layer graphene sheets were utilized to improve the thermal conductivity of C/SiC composites via an effective method to design graphene heat conductive channels. To determine the role of graphene sheets in improving thermal conductivity, the effect of the different loading fractions of graphene and microstructure of as-prepared composites were systemically investigated. Results revealed that the thermal conductivity of composites increased by 204% with well-designed graphene heat conductive channels. Besides, compared with the porosity, the orderly aligned heat conductive pathways played a more important role in thermal conductivity. This work provides a new and effective method for preparing well-designed heat conductive channels to enhance thermal conductivity of C/SiC.

AgNbO3-based ceramics have been the spotlight for the lead-free dielectric capacitors due to its unique antiferroelectric feature and the ever-increasing environmental concerns. Herein, synergic modulation on the energy storage properties of AgNbO3-based ceramics was reported, in which the over-stoichiometrical introduction of only 0.10 wt% MnO2 at the atomic-scale leads to reduced leakage current, Pr and enhanced antiferroelectric stability while the SiO2 coating on the AgNbO3 particles at the micro-scale greatly inhibits the grain growth, increases the breakdown strength and the electric filed inducing the AFE-FE transitions. As a result, a large recoverable energy density up to 3.34 J/cm3 with efficiency of 60.0% was obtained in 0.10 wt% MnO2-doped AgNbO3@SiO2 ceramic, which is 2.3 times larger than that of the pristine AgNbO3. This work provides a rational approach to synergically modulate the energy storage properties.

Headspace-gas chromatography-ion mobility spectroscopy (HS-GC-IMS) was used to detect the volatile organic compounds (VOCs) of yak milk powders (YMPs) under ultra-high-pressure sterilization (UHPS) and thermization (TH) methods. The analyses led to the identification of several characteristic of compounds, therefore, exploitation and comparison of the different flavors. A total of 46 peaks were detected, and 17 compounds were identified, including 7 aldehydes, 5 ketones, 3 acids, 1 terpene, and 1 ester. Furthermore, principal component analysis (PCA) and fingerprint similarity analysis based on Euclidean distance compared the YMPs and found that the YMPs had certain differences, which can distinguish the YMPs with different sterilization methods. In conclusion, different sterilization methods possibly affect the flavor of YMPs, and UHPS is bettedslfr than TH. Also, aldehydes were mainly be detected in UHPS groups, whereas the ketones and acids mostly appeared in TH groups. Most importantly, UHPS can retain the original flavor of yak milk to a greater extent.

Chiral separation has attracted much attention for basic research and industrial applications in analytical chemistry. Generally, chiral separations use natural or artificial chiral-based materials as adsorbents. To improve the precision and efficiency of chiral separation, focus has shifted from natural and synthetic adsorbents to binary combinations of materials. This review specifically summarizes the significant advancements made in natural and artificial chiral adsorbents as promising candidates for diverse drug and biomolecule separation applications as well as the remaining drawbacks and challenges for research on chiral separations. The mechanisms of chiral-based recognition and separation and history and development of natural and artificial chiral-based systems are the focus of this review. Future directions in natural and artificial chiral-based systems for practical separations and other applications are also presented.

Balancing selection is frequently invoked as a mechanism that maintains variation within and across populations. However, there are few examples of balancing selection operating on loci underpinning complex traits, which frequently display high levels of variation. We investigated mechanisms that may maintain variation in a focal polymorphism—leaf chemical profiles of a perennial wildflower (Boechera stricta, Brassicaceae)—explicitly interrogating multiple ecological and genetic processes including spatial variation in selection, antagonistic pleiotropy, and frequency-dependent selection. A suite of common garden and greenhouse experiments showed that the alleles underlying variation in chemical profile have contrasting fitness effects across environments, implicating two ecological drivers of selection on chemical profile: herbivory and drought. Phenotype-environment associations and molecular genetic analyses revealed additional evidence of past selection by these drivers. Together, these data are consistent with balancing selection on chemical profile, likely caused by pleiotropic effects of secondary chemical biosynthesis genes on herbivore defense and drought response., Editor’s Summary: Evidence for balancing selection acting on loci that control complex traits is limited. Here, the authors show evidence for past selection on chemical profile in a perennial wildflower by two ecological drivers, herbivory and drought, consistent with balancing selection on this trait.

The segregation behavior of trace amount of phosphorus (P) and the mechanical properties of dual-phase (DP) steels have been systematically studied. The microstructure of DP steels is mainly composed of martensite, ferrite and nanoscale carbides. For the DP steels with different trace amounts of P (≤ 0.015 wt%), P has almost no effect on the mechanical properties. Atom probe technology (APT) analyses confirm that P segregation was only found at the precipitate/matrix interface. Moreover, the precipitates of (Ti, Mo) C are widely distributed in the ferrite, martensite and ferrite/martensite interface regions. The special segregation feature of P would not concentrate at specific regions such as ferrite/martensite interface and/or martensite lath interface, which reveals that trace amounts of P (≤ 0.015wt%) have almost no effect on the mechanical properties of DP steels. It is proved for the first time that the MC-type carbides of (Ti, Mo) C can reduce or eliminate the damage effect of P on the mechanical properties of steels, which provides a new way for the design of alloys to reduce P damage. This work will promote to increase the P content control standard in DP steels from 0.01 to 0.015 wt%, which will not change the mechanical properties, but greatly reduce the scrap rate and increase the energy efficiency of the manufacturing process.

Mowing is a common management practice in grassland ecosystems. However, how mowing affects fine root dynamics remains poorly explored. A field experiment was conducted to study how mowing influences root dynamics in artificial and natural grasslands for three consecutive years with root-window method. Root production among the treatments varied from 312 to 681 m m−2 each year and fine root turnover varied between 1.58 and 3.41 times per year. Fine root production, root mortality and root standing crop exhibited clear seasonal patterns in both the natural and artificial grasslands, and these were mainly driven by precipitation and temperature. Root production and root turnover responded differently to mowing in different types of grassland. In the artificially restored grassland, mowing significantly increased root production and root turnover (15.01% and 13.06%, respectively) and decreased the root lifespan by 14.60%. In contrast, none these effects were significant in the naturally restored grassland. The mowing-induced increase in root production and root turnover in the artificially restored grassland was mainly due to an enhancement in aboveground biomass and soil moisture. However, the lack of an effect on these parameters from mowing in the naturally restored grassland may be due to the higher species diversity. Our findings demonstrate that mowing might accelerate root turnover and improve belowground productivity in the artificially restored grassland, highlighting that suitable mowing is an efficient way to manage artificial grasslands from the perspective of the dynamics of root system.

Sr(Mg1/2Mo1/2)O3 (SMM) microwave dielectric ceramic was prepared by a solid-state sintering method. X-ray diffraction shows that the sample is a single-phase SMM with a tetragonal double perovskite structure (Fm-3m). Raman scattering and FTIR spectroscopy analyze the vibration characteristics of lattice. The far-infrared spectra of SMM ceramics fitted by a FPSQ model are obtained, er = 7.39 and tanδ = 8.19 × 10–4. The theoretical properties calculated by the C-M and damping equations are of er = 7.03 and tanδ = 6.19 × 10–4, which agrees well with the experimental values (er = 7.84 and tanδ = 6.59 × 10–4). The results show that the stretching vibration of Mg/MoO6 has the greatest influence on the dielectric properties of the SMM sample.

NBT-xBT@BT-BZN composite ceramic materials were prepared by wet solid-phase reaction method. The effects of NBT-xBT (x = 6, 7, 8, 9 mol%) on the phase structure, morphology and dielectric propertie...

The identification of cone photoreceptor cells is important for early diagnosing of eye diseases. We proposed automatic deep-learning cone photoreceptor cell identification on adaptive optics scanning laser ophthalmoscope images. The proposed algorithm is based on DeepLab and bias field correction. Considering manual identification as reference, our algorithm is highly effective, achieving precision, recall, and F 1 score of 96.7%, 94.6%, and 95.7%, respectively. To illustrate the performance of our algorithm, we present identification results for images with different cone photoreceptor cell distributions. The experimental results show that our algorithm can achieve accurate photoreceptor cell identification on images of human retinas, which is comparable to manual identification.

The realization of a large low-field magnetoresistance (LFMR) effect in free-standing magnetic oxide films is a crucial goal toward promoting the development of flexible, low power consumption, and nonvolatile memory devices for information storage. La0.7Sr0.3MnO3 (LSMO) is an ideal material for spintronic devices due to its excellent magnetic and electronic properties. However, it is difficult to achieve both a large LFMR effect and high flexibility in LSMO films due to the lack of research on LFMR-related mechanisms and the strict LSMO growth conditions, which require rigid substrates. Here, we induced a large LFMR effect in an LSMO/mica heterostructure by utilizing a disorder-related spin-polarized tunneling effect and developed a simple transfer method to obtain free-standing LSMO films for the first time. Electrical and magnetic characterizations of these free-standing LSMO films revealed that all of the principal properties of LSMO were sustained under compressive and tensile conditions. Notably, the magnetoresistance of the processed LSMO film reached up to 16% under an ultrasmall magnetic field (0.1 T), which is 80 times that of a traditional LSMO film. As a demonstration, a stable nonvolatile multivalue storage function in flexible LSMO films was successfully achieved. Our work may pave the way for future wearable resistive memory device applications.

To illustrate the supramolecular catalysis process in molecular containers, two porphyrinatozinc(II)-faced cubic cages with different sizes were synthesized and used to catalyze acyl-transfer reactions between N-acetylimidazole (NAI) and various pyridylcarbinol (PC) regioisomers (2-PC, 3-PC, and 4-PC). A systemic investigation of the supramolecular catalysis occurring within these two hosts was performed, in combination with a host-guest binding study and density functional theory calculations. Compared to the reaction in a bulk solvent, the results that the reaction of 2-PC was found to be highly efficient with high rate enhancements (kcat/kuncat = 283 for Zn-1 and 442 for Zn-2), as well as the different efficiencies of the reactions with various ortho-substituted 2-PC substrates and NAI derivates should be attributed to the cages having preconcentrated and preoriented substrates. The same cage displayed different catalytic activities toward different PC regioisomers, which should be mainly attributed to different binding affinities between the respective reactant and product with the cages. Furthermore, control experiments were carried out to learn the effect of varying reactant concentrations and product inhibition. The results all suggested that, besides the confinement effect caused by the inner microenvironment, substrate transfer, including the encapsulation of the reactant and the release of products, should be considered to be a quite important factor in supramolecular catalysis within a molecular container.

Antibacterial packaging film mediated by photodynamic inactivation (PDI) is a new concept in food industry. The objective of this study was to fabricate a green 2,3-dialdehyde cellulose (DAC)-based antimicrobial film with PDI potency by incorporating the β-cyclodextrin/curcumin (β-CD/Cur) complex as a photosensitizer. The PDI-mediated films were characterized by evaluating the surface morphology, chemical structure, light transmittance, mechanical properties, photochemical and thermal stability, and water solubility. The results showed that the DAC-CD/Cur films were soluble in water and mechanically strong with a tensile strength of 63.87 MPa and an elongation break of 1.32%, which was attributed to the formation of hydrogen bonds between DAC and β-CD/Cur molecules. Meanwhile, the composite films possessed a good light transmittance but impeded the penetration of ultraviolet light and efficiently delayed the degradation of curcumin. More importantly, the PDI-mediated films exhibited a broad-spectrum ability to kill Listeria monocytogenes, Vibrio parahaemolyticus, and Shewanella putrefaciens in pure culture. Notably, they also potently inactivated these harmful bacteria on ready-to-eat salmon with a maximum of ∼4 Log CFU/g (99.99%) reduction after 60 min irradiation (13.68 J/cm2). Therefore, the PDI-mediated DAC-CD/Cur films are novel and promising antimicrobial food packaging films in food industry.

Poor interfacial bonding between diamond and matrices has limited industrial applications of diamond-containing composites. Herein, continuous and dense nanometer SiC coatings were deposited on both large size (200 μm) and small size (1.0 μm) diamond particles to improve the wettability of diamond and protect it from oxidation and graphitization. Coating procedure consisted of first pretreating diamond particles followed by chemical vapor deposition (CVD) using methyltrichlorosilane (MTS: CH3SiCl3) as a precursor. Effects of deposition temperature, time, and gas flowing rate on microstructures of SiC coatings were all studied. Results showed that diamond surfaces were fully coated by SiC with thicknesses of 30 nm and 20 nm for large and small size diamond particles, respectively. Meanwhile, onset oxidation temperatures of large and small SiC-coated diamond particles increased by 250 and 130 °C, showing greatly enhanced oxidation resistance than that of raw diamond particles. The compressive fracture strength (CFS) of SiC-coated diamond (200 μm) is 226 N, improved by 8.5% compared with that of the raw diamond (201 N). In sum, CVD method is promising for the preparation of homogeneous nanometer SiC coatings on diamond particles for its modification and further application in composites.

Ba2MgWO6 (BMW) microwave dielectric ceramic was prepared by the traditional solid-state sintering. According to the XRD pattern, the sample belongs to a double perovskite structure (Fm-3m). The SEM image shows that the ceramic is dense with high crystallinity, whose average particle size is of 3.22 μm. The lattice vibrational characteristics of BMW ceramic were identified and analyzed through Raman and FTIR spectroscopy, whose vibrational modes were determined. The intrinsic properties (er = 16.281, tanδ = 1.795 × 10−4) calculated from the FPSQ model based on the FTIR spectroscopy are close to the measured values (er = 16.95, tanδ = 2.44 × 10−4), and the dielectric response mainly comes from the modes of F1u(1) at 145 cm−1 and F1u(2) at 284 cm−1.

The Sip1Aa protein from Bacillus thuringiensis is highly toxic to Colaphellus bowringi Baly. In order to obtain mutant proteins with higher insecticidal activity, a random recombinant library of Sip1Aa protein was constructed using error-prone PCR. A total number of 100 positive transformants were randomly selected for sequence determination, and 25 mutants (M1 to M25) were selected and expressed the respective Sip1Aa mutants. These Sip1Aa variants had a total of 29 base mutations, with an average of 1.2 base mutations per mutant. Compared with that of the wild-type Sip1Aa protein, the insecticidal activity of the mutants M1 (A31G, Y118C, D227E), M5 (K168R) and M21 (I307T) was significantly decreased, with and LC50 values 4 to 6 times higher than the Sip1Aa protein. The mutant M8 (R174S) showed increase in the insecticidal activity against the Colaphellus bowringi Baly was obtained, with an LC50 value 4-fold less than the Sip1Aa protein. The results of this study provide reference for the molecular modification of Sip1Aa protein and the study of key sites of its insecticidal activity.

The systemic therapeutic utilisation of RNA interference (RNAi) is limited by the non-specific off-target effects, which can have severe adverse impacts in clinical applications. The accurate use of RNAi requires tumour-specific on-demand conditional activation to eliminate the off-target effects of RNAi, for which conventional RNAi systems cannot be used. Herein, a tumourous biomarker-activated RNAi platform is achieved through the careful design of RNAi prodrugs in extracellular vesicles (EVs) with cancer-specific recognition/activation features. These RNAi prodrugs are assembled by splitting and reconstituting the principal siRNAs into a hybridisation chain reaction (HCR) amplification machine. EVs facilitate the specific and efficient internalisation of RNAi prodrugs into target tumour cells, where endogenous microRNAs (miRNAs) promote immediate and autonomous HCR-amplified RNAi activation to simultaneously silence multiantenna hypoxia-related genes. With multiple guaranteed cancer recognition and synergistic therapy features, the miRNA-initiated HCR-promoted RNAi cascade holds great promise for personalised theranostics that enable reliable diagnosis and programmable on-demand therapy., The therapeutic application of small interfering RNA (siRNA) is challenging due to its non-specific targeting and delivery issues. Here, the authors report an endogenous micro-RNA guided and hybridisation chain reaction-promoted siRNA delivery system encapsulated in tumour-derived extracellular vesicles, with cancer-specific activation, and achieve silencing of hypoxia-related genes.

The accumulation of extracted titanium tailing (ETT) has seriously affected the local environment and human healthcare in the Panxi area of southwestern China. This research provides a practical way to convert ETT (up to high amount of 50 wt%) to high performance glass-ceramic by introducing waste glass (WG). The effects of sintering temperature and heat-treatment duration on the micro-structures and physicochemical properties of the produced glass-ceramic have been systematically investigated. It is found that the crystalline phase of the glass-ceramic has a great influence on the linear shrinkage rate and bulk density, further affecting its water absorption rate and hardness. The optimal product shows enhanced physical properties: linear shrinkage rate of 17.40 ± 0.04 %, bulk density of 2.75 ± 0.02 g cm-3, Vickers hardness of 21.3 ± 0.2 GPa and water absorption rate of 0.060 ± 0.002 % at the optimized sintering conditions. The formation mechanism of recycling two industrial wastes provides a guidance function to synthesize glass-ceramic using similar industrial waste residue and tailings. The obtained glass-ceramic with high performance has potential to be applied extensively in construction and building field.

Electrochemical machining (ECM) is an economical and effective method for blisk manufacturing and includes two steps: channel machining and profile machining. The allowance distribution after the channel machining will directly affect the profile machining. Therefore, to improve the uniformity of allowance distribution in the machining of channels, a method that incorporates a variable feed rate mode is developed. During the machining process, the feed rates are dynamically changed according to the needs of the side gap at the different feed depths. As a result, the side gaps at the different feed depths vary, contributing to a decrease in the allowance difference. In this study, the dissolution processes of a blisk channel are simulated using different feed rates, and prediction profiles are obtained. Based on the prediction profiles, the relationship among the feed rate, feed depth, and side gap is established. Then, the feed rates at different feed depths are adjusted according to the relationship. In addition, contrast experiments are conducted. Compared with blisk channel ECM using a constant feed rate of 1 mm/min, using the variable feed rate decreases the allowance differences in the convex and concave parts by 62.2 % and 67.4 %, respectively. This indicates that using the variable feed rate in the ECM process for a blisk channel is feasible and efficient.

Atom probe tomography, and related methods, probe the composition and the three-dimensional architecture of materials. The software tools which microscopists use, and how these tools are connected into workflows, make a substantial contribution to the accuracy and precision of such material characterization experiments. Typically, we adapt methods from other communities like mathematics, data science, computational geometry, artificial intelligence, or scientific computing. We also realize that improving on research data management is a challenge when it comes to align with the FAIR data stewardship principles. Faced with this global challenge, we are convinced it is useful to join forces. Here, we report the results and challenges with an inter-laboratory call for developing test cases for several types of atom probe microscopy software tools. The results support why defining detailed recipes of software workflows and sharing these recipes is necessary and rewarding: Open source tools and (meta)data exchange can help to make our day-to-day data processing tasks become more efficient, the training of new users and knowledge transfer become easier, and assist us with automated quantification of uncertainties to gain access to substantiated results.

The degradation mechanisms of 3-nitro-1,2,4-triazol-5-one (NTO) in the bulk water were explored at the density functional theory (DFT) level using the M06-2X functional and the 6-311G(d,p) basis set; the effect of bulk water solution was considered using the conductor-like polarizable continuum model (CPCM) approach. The initial dissociation step of NTO may be triggered by UV light, radicals, and heat. Our computed results suggest that radical-induced reactions should be suitable for the initial degradation of NTO in water. The follow-up further degradation illustrated that the product fragments may include urazole, NO, NO2, HONO, CO2, di-imide, and N2. It was revealed that hydroxide ions can accelerate the degradation of NTO in water.