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In this paper, quantum chemical calculations and Gaussian 09 software were used to investigate the similarities and differences in the reactive sites of different fatty acids. The molecule structures of linoleic acid (LA) and four conjugated linoleic acid (CLA) were analyzed at the level of density functional theory. Molecular geometries and energies, frontline molecular orbitals, and surface electrostatic potentials were also analyzed. The results showed that the reactive of LA and CLA among the five fatty acids were all near the –C = C– structure and the carboxyl hydrogen atom, 9c, 11t CLA and 10t, 12c CLA were more reactive compared with 9t, 11t CLA, 10t, 12t CLA. This study can provide a theoretical basis for revealing the relationship between different structures and properties of fatty acids and also provide a guidance for the selection of fatty acids in the oil and fat industry. Practical Applications: This experiment compares the differences between the reactive sites of CLA and the four CLAs at the molecular structure level, which can be used to deepen the understanding of the structure‐property relationship of different fatty acids and also provides a theoretical basis for the selection of fatty acids in the food and oil industry. [ABSTRACT FROM AUTHOR]

Karst environmental issues have become one of the hot spots in contemporary international geological research. The same problem of water shortage is one of the hot spots of global concern. The peak-cluster depression basins in southwest of Guangxi is an important water connotation and ecological barrier areas in the Pearl River Basin of China. Thus, studying the spatial and temporal variations and the influencing factors of its water yield services is critical to achieve the sustainable development of water resources and ecological environmental protection in this region. As such, this paper uses the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model to assess the spatial and temporal variabilities of water yield services and its trends in the peak-cluster depression basins in southwest of Guangxi from 2000 to 2020. This work also integrates precipitation (Pre), reference evapotranspiration (ET), temperature (Tem), digital elevation model (DEM), slope, normalized difference vegetation index (NDVI), land use/land cover (LULC) and soil type to reveal the main factors that influence water yield services with the help of Geodetector. Results show that: 1) in time scale, the total annual water yield in the study area show a fluctuating and increasing trend from 2000 to 2020, with a growth rate of 7.3753 × 108 m3/yr, and its multi-year average water yield was 538.07 mm; 2) in spatial pattern, with high yield areas mainly distributed in the south of the study area (mainly including Shangsi County, Pingxiang City, Ningming County, Longzhou County and Jingxi County), and low yield areas mainly distributed in Baise City and Nanning City; 3) the dominant factor of water yield within karst and non-karst landforms is not necessarily controlled by precipitation, and the explanation degree of DEM factors in karst areas is significantly higher than that in non-karst areas; 4) amongst the climatic factors, Pre, ET and Tem are dominant in the spatial pattern of region water yield capacity. among which Pre has the highest explanatory power for the spatial heterogeneity of annual water production, with q values above 0.8, and each driver showed a significant interaction on the spatial distribution of water yield, with Pre exhibiting the strongest interaction with LULC. [ABSTRACT FROM AUTHOR]

• A comprehensive stiffness model of intermediate bearing is presented. • A reduced model of dual rotor-bearing-casing coupling system is developed. • The effects of typical parameters on the vibration of the system are discussed. • The mechanism of the comprehensive stiffness and system vibration is revealed. This paper focuses on the vibrational properties of a dual rotor-casing coupled system with nonlinear clearance in the intermediate bearing, considering both the oil film stiffness and Hertzian contact stiffness between rolling elements and raceways. A comprehensive stiffness model for the intermediate bearing has been developed based on elastohydrodynamic lubrication (EHL) and Hertz contact theory. Subsequently, a dynamical model of the dual rotor-bearing-casing system is established using the finite element method, thereby verifying the feasibility of simulating the casing with beam elements. The dimensionality of the system equation is reduced using the fixed-interface component mode synthesis (CMS) method, and the resulting reduced-dimensionality equation is solved using the improved Newmark- β method. The effects of casing support, rotational speed, and radial clearance on the vibration characteristics of the system are investigated. Then, the comprehensive stiffness and coupled vibration characteristics of the system are analyzed to elucidate its intrinsic mechanism. Finally, the contact characteristics within the intermediate bearing under dynamic load are also studied. The results indicate that the support stiffness of the casing has a more significant impact on the second resonance caused by both the inner and outer rotors. The system is prone to experiencing varying compliance (VC) resonance at low rotational speeds. The excessive bearing clearance leads to complex vibrational characteristics of the system, making it challenging to predict its motion. The impact of minor changes in stiffness on system vibration is small when the comprehensive stiffness is large. At this time, the limited effect of oil film stiffness allows it to be disregarded in terms of comprehensive stiffness. Furthermore, the speed significantly influences the contact characteristics within the intermediate bearing under the unbalanced force of the rotor and gravity. [ABSTRACT FROM AUTHOR]

Adversarial examples have a simple additive structure that the clean sample is added with delicate devised noise. Inspired by such an observation, we find that the prediction of the network on adversarial examples can also be decoupled into a simple additive structure, which is the sum of clean samples and adversarial perturbations in terms of the model prediction (called the decoupling principle). Thus, our findings can be served as a useful tool to gain insight into the underlying relationship between the inputs and the outputs of the model. However, although the adversarial examples generated by existing attack methods can satisfy the decoupling principle, the proportion is small. In this paper, we formulate the above issues as an optimization problem with multi-constrains, and we propose a generative model to generate adversarial examples that satisfy the decoupling principle and simultaneously obtain high attack performance. Specifically, we first adopt the adversarial loss to ensure the attack performance. Then, we devise a decouple loss to guarantee the decoupling principle. Moreover, we treat the Euclidean distances of perturbation as regularization terms to maintain visual quality. Extensive experiments against various networks on ImageNet and CIFAR10 show that the proposed method performs better than comparison methods in the comprehensive metric. Furthermore, transferability results suggested that adversarial examples that satisfy the decoupling principle show better transferability. • We find that the prediction of adversarial examples can be decoupled into the summation of clean samples and perturbations in terms of the model prediction, which can be a useful tool to gain insight into the underlying relationship between the inputs and the outputs. • We propose a generative model-based method to craft the adversarial perturbation, which satisfies the decoupling principle and simultaneously has superior attack performance. Moreover, the decouple loss is devised to guide the generative model for ensuring the decoupling principle. • We conduct extensive experiments against different networks on the complex ImageNet and simple CIFAR10 datasets. Experiment results suggest that the proposed method outperforms the comparison methods by a large margin in the devised metric that balance the attack performance and decoupling principle. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of forecasting crude oil prices, a new crude oil price forecasting method is introduced in the paper that is a combination of the FNN model and the stochastic time effective function—namely, the WT-FNN model. The FNN model keeps track of the historical values of crude oil prices and predicts future crude oil prices, and the stochastic time effective function gives greater weight to recent information and smaller weight to old information, thus making the prediction of crude oil prices more reasonable. We selected the daily data of Brent crude oil prices from 4 January 2000 to 30 September 2021 as research objects and then used the WT-FNN model to train and predict the research objects. By comparing it to the benchmark model, we found that the predictive effect of the WT-FNN model was better than the FNN model and the no-change model. The results also passed a robustness test. [ABSTRACT FROM AUTHOR]

Wide deployment of deep neural networks (DNNs) based applications (e.g. , style transfer, cartoonish), stimulating the need for copyright protection of such application's production. Though some traditional visible copyright techniques exist, they often introduce undesired artifacts and compromise the aesthetic quality of the images. In this paper, we propose a novel invisible, robust copyright protection method, which is composed of two networks: the copyright encoder and the copyright decoder. The former projects the copyright information to the invisible perturbation with the drive of both the input of images and copyright information, thereby adding it to the image and yielding encoded images. The copyright decoder extracts copyright information from encoded images. Moreover, a robustness module is integrated to enhance the decoder's ability to decipher images against various distortions encountered on social media platforms. Furthermore, the loss function is elaborately designed, taking into account both feature space and color space, to guarantee the quality of encoded and decoded copyright images. Extensively objective and subjective experiments validate the effectiveness of the proposed method. Additionally, the physical test is conducted by posting the encoded images to social media (e.g. , Weibo and Twitter) and downloading them to verify the feasibility of the proposed method in practice. [ABSTRACT FROM AUTHOR]

Two kinds of SiC nanowires exhibiting different structures were fabricated by carbothermal reduction method and subsequent wet chemical etching. Strong and tunable ultraviolet to green emission peaks emerged in the photoluminescence spectra of both kinds of SiC nanowires in water and ethanol suspensions with the increase of excitation wavelength from 260 nm to 480 nm. The strong and distinctive ultraviolet emission originates from the quantum confinement effect of the nanoplatelets with a thickness less than 3 nm and the effects of Si–OH and Si–OR (R: ethoxy group) on the SiC nanowire surface. The blue emission derived from the SiC nanowires in different solvents is due to the combined effect of the nanoplatelet thickness, which meets the theoretical prediction value (3–5.4 nm), and surface bonds. The weaker green emission can be attributed to the large SiC nanowires and surface bonds caused by Si–OR and Si–OH. [ABSTRACT FROM AUTHOR]

Characterizing the availability of opportunities to residents has been a long-term aim in health care geographic investigation. It is important to measure the degree of inequity in health care accessibility and to identify underserved areas, due to the uneven distribution of health care services. In this study, JavaScript was used to calculate travel time based on Amap, as this can provide a more reliable data support to measure the health care accessibility in Xi'an communities, China. Based on the overall equity, herein, an attempt was made to quantify the equity of health care accessibility, and to identify health care underserved areas inside the different communities. Results show that the accessibility to low-level health care services is high in the northern areas and low in the southern areas, while the accessibility to high-level and comprehensive health care services shows a clear core-periphery spatial structure. Moreover, the overall equity of the health care accessibility is relatively low, and the inequity of high-level health care accessibility is further aggravated. Furthermore, the quantified equity of accessibility to high-level and comprehensive health care services in the central urban areas is better; however low-level health care services are relatively inadequate. There are significant differences among health care underserved areas, in particular, for the worst equity and the lowest accessibility areas (A1) and the worse equity and the lowest accessibility areas (B1) in high-level underserved areas. Notably, the sharing of health care services and the reasonable flow of health technical personnel among different levels of health institutions can make the high-level health care services in the central urban areas have a greater trickle effect on the surrounding areas. [ABSTRACT FROM AUTHOR]

Fully grouted anchor systems have been widely used for stability control at earthen sites. The bond performance between the bolt and the slurry, which is determined from the bolt type, bolt diameter, slurry thickness and bond length, has an important influence on the anchor performance and working mechanism of the anchor system. This paper considers three anchor systems consisting of different types of bolts and modified glutinous rice slurry. To test the relevant physical and mechanical indexes of the soil for a site, the slurry and bolts, in situ anchor, pull-out tests and stress–strain monitoring of the bolt–slurry interface are conducted for anchor systems in terms of the bolt diameter, slurry thickness and bond length. The influence of various parameters on the bond strength between the bolt and the slurry is quantitatively analysed based on the test results, while the distributions of the bond stress between the bolt and the slurry along the bond length are qualitatively analysed. The bond mechanisms between the bolt and the slurry for different bolt types with the anchor systems are discussed, and optimal matching values for the anchor parameters with each bolt type are proposed. [ABSTRACT FROM AUTHOR]

Based on the discovery of the "natural orange soil layer" in the wall foundation of the Ming Great Wall in Huangzhong County, Xining City, northwest China, this paper reveals the mechanism behind the barrier effect of this layer on the salinity deterioration through the combination of qualitative judgment and quantitative testing. Based on this mechanism, the conventional lime soil was improved by adding modified polyvinyl alcohol as the cementing agent and fly ash, thereby generating a modified cushion material. Indoor tests of freeze-thaw and temperature-humidity cycles for the modified cushion material were then conducted alongside field tests of rammed restorations in the basal sapping zone with and without the modified cushion. The test results show that the modified cushion materials have excellent durability and act as a substantial barrier to salinity deterioration. The research results provide a new approach to repairing the basal sapping of earthen sites. [ABSTRACT FROM AUTHOR]

In this paper, we present the construction of the rational solutions to the nonlocal nonlinear Schrödinger equation by the bilinear method and KP reduction method. The solutions are given in determinant form, the first- and second-order rational solutions are analyzed for their dynamic behaviors. [ABSTRACT FROM AUTHOR]

Two types of SiC nanowires were synthesized via carbothermal reduction and subsequent wet chemical etching. Both SiC nanowires consisted of cubic β-SiC and exhibited numerous stacking fault nanolayers. The etching process was very selective to the stacking fault nanolayers and β-SiC; β-SiC was gradually corroded; however, the stacking faults were retained. Three strong and distinct photoluminescence (PL) emission peaks emerged in the PL spectra of both types of SiC nanowires as the excitation wavelength was increased from 290 to 490 nm. The strong ultraviolet emission and the blueshift of the PL peak were related to the quantum confinement effects of the stacking fault nanolayers having a thickness of <3 nm. This quantum confinement effect was responsible for the blue emission observed from the SiC nanowires. The thickness of the nanolayers was in good agreement with the theoretically predicted value (3–5.4 nm). The additional green emission and blueshift of the peak arose from surface structures induced by Si O and Si-OH. The green emission required a sufficiently large surface area and was only observed using longer-wavelength excitation to excite more SiC nanowires with larger sizes. • Photoluminescence (PL) of two types of SiC nanowires were evaluated at room temperature. • The strong ultraviolet emission and the blueshift of the PL peak due to the stacking fault nanolayers having a thickness of <3 nm. • The blue emission were related to the thickness of the nanolayers which in good agreement with the theoretically predicted value (3–5.4 nm). • The green emission and blueshift of the peak arose from surface structures induced by Si O and Si-OH. [ABSTRACT FROM AUTHOR]

• Rice bran protein-tannic acid emulsions were treated with ultrasound. • Ultrasonic treatment improved microstructure and properties of emulsions. • The best emulsion properties were obtained at an ultrasonic power of 400 W. Rice bran protein (RBP)-tannic acid (TA) complex was prepared and the RBP-TA emulsions were subjected to ultrasonic treatment with different powers. Ultrasonic treatment has a positive effect on improving the properties of RBP-TA emulsion. This study investigated the influence of different ultrasonic power levels on the physicochemical properties, microstructure, rheological properties, and stability of emulsions containing RBP-TA. Under the ultrasonic treatment of 400 W, the particle size, zeta potential, and adsorbed protein content of the RBP-TA emulsion were 146.86 nm, −20.7 eV, and 61.91%, respectively. At this time, the emulsion had the best emulsifying properties, apparent viscosity, energy storage modulus and loss modulus. In addition, the POV and TBARS values of RBP-TA emulsions were 6.12 and 7.60 mmol/kg, respectively. The thermal, salt ion, pH and oxidative stability of the emulsions were investigated, and it was shown that ultrasonic treatment was effective in improving the stability of RBP-TA emulsions. [ABSTRACT FROM AUTHOR]

In this study, the structure and flavor characteristics of soybean meal hydrolysates-reducing sugars Maillard reaction products (MRPs) were evaluated. Sugars added to the soybean meal enzymatic hydrolysates increased the Maillard reactivity in the following order: hexose < pentose. Results indicated that the intrinsic fluorescence intensity of MRPs increased, whereas the absorption peak intensity of the infrared spectrum changed significantly. Molecular weight analysis results showed that the MRPs were mainly distributed between 128-500 and 500–1000 Da. Furthermore, the bitter amino acid content (9.29 mg/g) and umami amino acid content (3.60 mg/g) were relatively high in ribose-MRPs. The umami, richness and bitterness values of pentose-MRPs were higher than those of hexose-MRPs. Moreover, the analysis of volatile substances showed that the ribose-MRPs presented a stronger caramel aroma, nutty flavor, and grilled meat flavor. • Reducing sugar types affected the structure and flavor of Maillard reaction products. • Soybean meal enzymatic hydrolysates were prepared by two-step enzymolysis. • Maillard reaction products were mainly distributed between 128-500 and 500–1000 Da. • Ribose-Maillard reaction products showed a stronger flavor characteristic. [ABSTRACT FROM AUTHOR]

We modify a simple agent-based model (ABM) proposed by Franke and Westerhoff [J. Econ. Dyn. Control, 2012, 36(8), 1193-1211] through considering the price limits and the motion of the fundamental value. The method of simulated moments is applied to calibrate both initial and modified ABMs with CSI 300 and S&P 500 respectively, and the goodness-of-fit of each ABMs is tested. The calibration results indicate that the modified model performs better than initial one. Then, we utilize the GSL-div, proposed by Lamperti [Econometrics Stat, 2018, 5, 83-106.], to verify the explanatory power of ABMs. In this procedure, 13 ARCH family models are introduced as benchmarks. The result shows that the explanatory power of modified ABM exceeds ARCH models in both markets, while initial ABM may be defeated by some of the ARCH family models in explaining the microstructure of CSI 300. Finally, a heuristic algorithm is designed to disentangle the insights of Chinese and US stock markets to the observed time horizon through calibrating the initial fundamental value, and Kupiec test is used to check the robustness of the calibration. The result indicates that the explanation of modified model is robust in both markets, while initial model lost its robustness when explaining S&P 500. [ABSTRACT FROM AUTHOR]

Developing highly porous and conductive carbon electrodes are crucial for high-performance electrochemical double-layer capacitors. Herein, we provide a supercapacitor electrode material consisting of N-doped porous carbon tightly anchored on carbon nanotubes. This nanocomposite with high specific surface area of 659.5 m 2 g −1 is fabricated by pyrolyzing the ZIF-8/polypyrrole nanotubes. When the nanocompiste is used as supercapacitor electrodes, it deliveres high specific capacitance of 248 F g −1 and 97.3% of capacitance retention after 3000 cycles. The superior capacitive performance is attributed to the conductive network for electron transport constributed by CNTs and the abundant reservoir for the charge storage derived from ZIF-derived porous carbon. Benefiting from the unique structural features and high N doping, the PC-CNTs obtained by our route could be a promising candidate of electrode mateials for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

In this paper, free vibration and transmission properties of single and composite thin annular plate (TAP) structures are presented by wave approach. The propagation matrix, continuity matrix and reflection matrix are introduced to carry out the analysis. Using the wave approach, natural frequencies of single and composite TAP are calculated theoretically. The results obtained by this method agree well with those calculated by the classical Bessel and Hankel methods. Additionally, transfer matrix is introduced and combined with the boundary conditions to obtain the transmission behaviors of composite multilayer TAP. To thoroughly understand the composite TAP, the influences of thickness, density ratio and radius ratio on natural frequencies are investigated. This study provides very useful information for transverse vibration suppression of TAP structure. [ABSTRACT FROM AUTHOR]

N-doped porous carbon nanosheets (N-CNS) were prepared from coal tar pitch with the addition of urea and KOH activation. In the synthesis route, urea plays an important role in constructing the 2D sheet-like structure, which serves as a nitrogen source, chemical blowing agent and the in-situ formation of g-C 3 N 4 self-degraded template. At a low activation temperature (600 °C), the as-prepared N-doped porous carbon nanosheets possess high nitrogen content (7.06 at. %) and high specific surface area (1181 m 2  g −1 ), which offers remarkable capacitive performances due to the unique architecture and pseudocapacitance contribution of the N doping. The N-CNS exhibits high capacitive performance (210 F g −1 at 0.1 A g −1 ), and an excellent cycling stability. Additionally, the assembled symmetric supercapacitor displays an energy density of 7.15 Wh kg −1 , and the capacitance retention remains 91.2% after 5000 cycles at 1 A g −1 . The facile and low-cost route to massively prepare N-doped porous carbon nanosheets from coal tar pitch would be favorable to the applications of carbon materials for high performance supercapacitors. [ABSTRACT FROM AUTHOR]

Based on historical data of operational risk in Chinese commercial banks between 1994 and 2012, this paper introduces Lévy measure to describe discontinuous jumping behavior of operational losses, uses thinning method to simulate the dynamical process of operational risk losses and adopts Lévy Copula model considering frequency dependence and severity dependence simultaneously. In this paper, a dynamical operational risk model with time-varying parameters and time-varying correlation structure is given as well as the corresponding numerical experimental technology to calculate VaR and CVaR in different confidence levels. The empirical result shows that Lévy Copula model of which setting risk is decreased shows priority in describing the dependence structures between risk cells. In comparison with traditional Copula model, Lévy Copula model depicts dependence structure more explicitly and intensively lowering total risk capital and passes model robustness test as well. Furthermore, the dynamical Copula model displays trends of risk and reduces the estimation bias of risk capital deriving from time-varying parameters. [ABSTRACT FROM AUTHOR]

• Single atom catalyst with Co-N 4 coordination has been precisely synthesized. • The interconnected 2D network can alleviate the formation of Li-dendrites. • Co-N 4 center suppress the shuttle effect and reduce the reaction energy barrier. • The correlation between the Co-N 4 sites and catalytic activity is deciphered. • The batteries exhibit superior electrochemical performance. Developing electrocatalyst to ameliorate the shuttling effect of lithium polysulfides (LiPSs), sluggish sulfur redox reaction kinetics and the rampant dendrite growth is of paramount importance for lithium-sulfur (Li-S) batteries. Yet still, the utilization of the most mainstream traditional metal electrocatalytic nanoparticles is far below expectation. Herein, we engineer an exclusive single-atom catalyst with planar Co-N 4 coupling of nitrogen-doped graphene mesh (SA-Co/NGM) to achieve exceptional atom utilization efficiency for catalytic conversion of LiPSs. High surface area and ultra-thin two-dimensional texture can not only accommodate high concentration monodispersed lithiophilic atomic Co sites, but also guarantee homogenize high-flux Li ion transport, alleviating the formation of Li-dendrites. Critically, the maximized exposure of Co-N 4 as a regulator in sulfur electrochemistry can conspicuously suppress the shuttle effect and accelerate bidirectional sulfur redox kinetics via electron delocalization, as demonstrated by a judicious combination of electro-kinetic analysis, in situ spectroscopy and density functional theory (DFT) computations. As expected, the batteries based on a SA-Co/NGM modified separator achieve an ultrahigh rate capability, exceptionally long cycle life and a distinguished favorable areal capacity under high sulfur loading. This work provides a rational design of single-atom catalysts for kinetics-boosted electrocatalysis towards long-lasting Li-S batteries. [ABSTRACT FROM AUTHOR]

Switchgrass ( Panicum virgatum L.) is a sustainable cellulosic energy crop with high biomass yield on marginal soils. Tillering, an important agronomic characteristic related to biomass production in gramineous plants, is regulated by complex interacting factors, such as plant hormones. Strigolactones (SLs) comprise a novel class of plant hormones that inhibit shoot branching. The MORE AXILLARY GROWTH2 ( MAX2 )/ DWARF 3 ( D3 )/ RAMOSUS ( RMS4 ) genes encode proteins involved in the SL signaling pathway in various plants. The switchgrass tetraploid genome likely contains two high-similarity MAX2 homologs, one of which is 6 bp longer than the other. The longest is named PvMAX2 and is the ortholog of MAX2 in Arabidopsis, D3 in rice, and RMS4 in petunia. PvMAX2 is expressed ubiquitously in switchgrass tissues, with higher expression levels observed in the stem and shoot. PvMAX2 gene expression is upregulated by GR24, a synthetic SL analog. Ectopic expression of PvMAX2 in the Arabidopsis max2 mutant rescued the dwarf and bushy phenotypes and small leaf size in the mutant, suggesting that functions of AtMAX2 in Arabidopsis are conserved in PvMAX2 . Ectopic PvMAX2 expression also restored the wild-type primary root and hypocotyl length phenotypes and restored the response to GR24. These results indicate that PvMAX2 may play an important role in switchgrass tillering through the SL pathway. [ABSTRACT FROM AUTHOR]

Based on daily and one-minute high-frequency returns, this paper examines the lead–lag dependence between the CSI 300 index spot and futures markets from 2010 to 2014. A nonparametric and non-linear method based on the thermal optimal path method is adopted. Empirical results of the daily data indicate that the lead–lag relationship between the two markets is within one day but this relationship is volatile since neither of the two possible situations (the futures leads or lags behind the spot market) takes a dominant place. Our results using the high-frequency data demonstrate that there is a price discovery in the Chinese futures market: the intraday one-minute futures return leads the cash return by 0–5 min regardless of the price trend of the market. [ABSTRACT FROM PUBLISHER]

Radial vibration of the circular plate is presented using wave propagation approach and classical method containing Bessel solution and Hankel solution for calculating the natural frequency theoretically. In cylindrical coordinate system, in order to obtain natural frequency, propagation and reflection matrices are deduced at the boundaries of free-free, fixed-fixed, and fixed-free using wave propagation approach. Furthermore, radial phononic crystal is constructed by connecting two materials periodically for the analysis of band phenomenon. Also, Finite Element Simulation (FEM) is adopted to verify the theoretical results. Finally, the radial and piezoelectric effects on the band are also discussed. [ABSTRACT FROM AUTHOR]

Dietary composition and rearing regime largely determine the trace elemental composition of pigs, and consequently their concentration in animal products. The present study evaluates thirteen macro- and trace element concentrations in pork from organic and conventional farms. Conventional pigs were given a commercial feed with added minerals; organic pigs were given a feed based on organic feedstuffs. The content of macro-elements (Na, K, Mg and Ca) and some trace elements (Ni, Fe, Zn and Sr) in organic and conventional meat samples showed no significant differences (P > 0.05). Several trace element concentrations in organic pork were significantly higher (P < 0.05) compared to conventional pork: Cr (808 and 500 μg/kg in organic and conventional pork, respectively), Mn (695 and 473 μg/kg) and Cu (1.80 and 1.49 mg/kg). The results showed considerable differences in mineral content between samples from pigs reared in organic and conventional systems. Our results also indicate that authentication of organic pork can be realized by applying multivariate chemometric methods such as discriminant analysis to this multi-element data. [ABSTRACT FROM AUTHOR]

As for studying the sub-harmonic and super-harmonic periodic motions, eigenvalue dynamics and period-doubling bifurcation tree of the nonlinear rotor system, an implicit discrete mapping method is applied to a nonlinear sliding bearing–rotor system. The nonlinear term of the rotor system is triggered by the oil film forces of the sliding bearing at both ends. In order to accurately reveal the dynamic characteristics of the system, in this paper, a thirteen-parameter polynomial oil film force model is proposed. It considers the effects of displacement and velocity on the oil film force. And, the discrete mapping method used in this paper is a semi-analytical tool for solving equations with high precision. Consequently, continuous eigenvalue diagrams and bifurcation trees of periodic solutions from Period-1 to Period-4 motions of the nonlinear rotor system are obtained. For verification, numerical simulations are completed. Numerical and semi-analytical results are compared in time–history displacement, velocity and trajectories. Furthermore, the active feedback controller is carried out to improve the stability of the system. • An implicit discrete mapping method is applied to a nonlinear sliding bearing–rotor system. • The nonlinear term of the rotor system is triggered by the oil film forces of the sliding bearing at both ends. And, the oil film force model is proposed as a thirteen-parameter polynomial in this paper. • Continuous eigenvalue diagrams and bifurcation trees of periodic solutions from Period-1 to Period-4 motions of the nonlinear rotor system are obtained. [ABSTRACT FROM AUTHOR]

The photogalvanic effect (PGE) generated under linearly polarized light irradiation has remarkable applications in 2D nanodevices. The PGE of 2D WS2/Mo2CF2 van der Waals (vdW) heterostructure can generate photocurrent and high sensitivity to polarized light. However, the PGE has less photogenerated current. On this basis, the photocurrent transport mechanism of PGE under low bias voltage is investigated. The results show that the photocurrent of the photon energy has cos2θ, sin2θ and sin2θ dependence on the polarization angle θ under the considered external bias voltage. Under a bias voltage of 1.0 V, the maximum photocurrent of 3.7 eV photon energy in the zigzag direction can reach 4.61. Under a bias voltage of 1 V, the maximum photocurrent of 1.8 eV photon energy in the armchair direction can reach 6.71. The maximum photocurrents are in the order of 10−1 for both zigzag and armchair directions with 0 V bias. Furthermore, 2D WS2/Mo2CF2 vdW heterostructure has a stable and high extinction ratio. These results show that 2D WS2/Mo2CF2 vdW heterostructure is a potential candidate material for future optoelectronics in the visible light region. [ABSTRACT FROM AUTHOR]

• A three-dimensional Ni,Co-embedded CNT-coated N-doped hollow porous carbon (Ni/Co-CNT/NHPC) cathode has been designed and prepared for lithium-sulfur battery. • The Ni/Co-CNT/NHPC-S cathode possesses a high specific capacity of 1352 mA h g-1 and an excellent cycle stability at 1 C with low capacity decay of 0.094% per cycle over 500 cycles. • The mechanism of suppressing the shuttle effect on the cathode materials is discussed by analyzing adsorption experiments and density functional theory（DFT）calculation. Lithium-sulfur (Li-S) batteries have attracted great attentions due to their high specific capacity. However, the poor cycle stability caused by polysulfide shuttles, volume expansion and formation of lithium dendrites limit their practical applications. In the present work, to tackle the poor stability and unstable rate capability, a MOF-doping strategy is developed to construct a hollow porous carbon framework，which consists of Ni, Co particles and CNT on a N-doped shell surface (Ni/Co-CNT/NHPC). This hollow framework increases the load of S, slows down the volume changes, and can physically entrap soluble polysulfide. It is found that the CNT-coated network structure is beneficial for optimizing the conductivity and wettability of the material, which accelerates the reaction kinetics. Moreover, synergistic effect of abundant defects and Ni, Co nanoparticles strengthens the chemisorption of polysulfides, which suppresses the shuttle effect. As a consequence, the Ni/Co-CNT/NHPC-S cathode harvests a high specific capacity (1352 mA h g-1), and shows an excellent cycling stability at 1 C with low capacity decay of 0.094% over 500 cycles. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) heterostructures have attracted much attention due to their unique properties in photocatalysis, electronics, and energy storage. This work comprehensively analyzed the electronic properties and photocatalytic efficiency properties of 2D vdW MoS2/Hf2CO2 heterostructure by first-principles calculations and molecular dynamics simulation. An ideal band gap of 1.44 eV was found for visible light absorption. Meanwhile, a high solar-to-hydrogen efficiency of 17.14% is obtained from the calculated band-edge positions, and a high power conversion efficiency of 13.84% is also confirmed by spectroscopy limited maximum efficiency simulation. We estimate the time scale for electron–hole transfer and recombination times using a combination of non-adiabatic molecular dynamics and time-dependent density functional theory. A suitable e-h recombination time of 1.86 ns and electron (hole) transfer time of 331 (978) fs are obtained in the 2D MoS2/Hf2CO2 heterostructure, which is expected to ensure high photocatalytic efficiency. Therefore, the constructed MoS2/Hf2CO2 heterostructures provide a new example for the prediction of high-performance nano optoelectronic devices. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) heterostructures have attracted much attention due to their unique properties in photocatalysis, electronics, and energy storage. This work comprehensively analyzed the electronic properties and photocatalytic efficiency properties of 2D vdW MoS2/Hf2CO2 heterostructure by first-principles calculations and molecular dynamics simulation. An ideal band gap of 1.44 eV was found for visible light absorption. Meanwhile, a high solar-to-hydrogen efficiency of 17.14% is obtained from the calculated band-edge positions, and a high power conversion efficiency of 13.84% is also confirmed by spectroscopy limited maximum efficiency simulation. We estimate the time scale for electron–hole transfer and recombination times using a combination of non-adiabatic molecular dynamics and time-dependent density functional theory. A suitable e-h recombination time of 1.86 ns and electron (hole) transfer time of 331 (978) fs are obtained in the 2D MoS2/Hf2CO2 heterostructure, which is expected to ensure high photocatalytic efficiency. Therefore, the constructed MoS2/Hf2CO2 heterostructures provide a new example for the prediction of high-performance nano optoelectronic devices. [ABSTRACT FROM AUTHOR]

Islet transplantation has great potential for curing type 1 diabetes; however, long-term islet survival using conventional immunosuppression remains elusive. We present a novel strategy for inducing long-lasting islet graft survival in diabetic NOD mice in the absence of posttransplant immunosuppression by initial treatment with antilymphocyte serum (ALS) followed by coadministration of donor pancreatic lymph node cells (PLNCs). When treated with ALS/PLNC, diabetic NOD mice become normoglycemic and tolerated minor antigen-disparate islet grafts for >100 days and syngeneic islet grafts indefinitely. Donor T-cells are required for graft prolongation, and tolerant hosts have long-term donor T-cell chimerism. Strikingly, host autoreactive T-cells from mice with long-surviving islet grafts predominantly produce interleukin-4, whereas autoreactive T-cells from mice that rejected their islet grafts predominantly produce interferon-gamma. We thus demonstrate a clinically relevant approach for ablation of recurrent autoimmunity in islet transplantation, involving donor lymphocyte-driven alteration of pathogenic autoreactive T-cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stability, degradation and in vitro simulation characteristics of emulsions. • Oleogel-in-water emulsion with 3 % hemp seed protein had better stability. • The half-life of cannabinol in oleogel-in-water emulsion was 131.82 days. • Bioaccessibility of cannabinol in oleogel-in-water emulsion was 58.0 %. The present study focused on investigating the stability and in vitro simulation characteristics of oil-in-water (O/W) and oleogel-in-water (Og/W) emulsions. Compared with O/W emulsion, the Og/W emulsion exhibited superior stability, with a more evenly spread droplet distribution, and the Og/W emulsion containing 3 % hemp seed protein (HSP) showed better stability against environmental factors, including heat treatment, ionic strength, and changes in pH. Additionally, the stability of Δ9-tetrahydrocannabinol (Δ9-THC) and cannabinol (CBN) and the in vitro digestion of hemp seed oil (HSO) were evaluated. The half-life of CBN in the Og/W emulsion was found to be 131.82 days, with a degradation rate of 0.00527. The in vitro simulation results indicated that the Og/W emulsion effectively delayed the intestinal digestion of HSO, and the bioaccessibility of Δ9-THC and CBN reached 56.0 % and 58.0 %, respectively. The study findings demonstrated that the Og/W emulsion constructed with oleogel and HSP, exhibited excellent stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A double carbon encapsulated porous composite with compact interface was designed. • The P-Si@rGO@C electrode exhibited inspiring rate-capability and long-cycling life. • The storage mechanism was explored via reaction kinetics, Ex-situ tests, and DFT. • A Li x Si prelithiation suspension was provided to enhance the ICE of the full cell. Developing high-performance composites with fast charging and superior cycle life is paramount for lithium-ion batteries (LIBs). Herein, we synthesized a double-shell carbon-coated porous structure composite with a compact surface (P-Si@rGO@C) using low-cost commercial micron-sized silicon (Si) instead of nanoscale silicon. Results reveal that the unique P-Si@rGO@C features high adaptability to volume expansion, accelerates electron/ion transmission rate, and forms a stable solid electrolyte interphase (SEI) film. This phenomenon arises from the synergistic effect of abundant internal voids and an external double-layer carbon shell with a dense surface. Specifically, the P-Si@rGO@C anode exhibits a high initial coulombic efficiency (ICE) (88.0 %), impressive rate-capability (612.1 mAh/g at 2C), and exceptional long-term cyclability (972.2 mAh/g over 500 cycles at 0.5C). Further kinetic studies elucidate the diffusion-capacitance hybrid energy storage mechanism and reveal an improved Li+ diffusion coefficient (from 3.47 × 10-11 to 2.85 × 10-9 cm2 s-1). Ex-situ characterization confirms the crystal phase change of micron-sized Si and the formation of a stable LiF-rich SEI. Theoretical calculations support these findings by demonstrating an enhancement in the adsorption ability of Si to Li+ (from -0.89 to -0.97 eV) and a reduction in the energy migration barrier (from 0.35 to 0.18 eV). Additionally, practical Li x Si powder is shown to increase the ICE of full cells from 67.4 % to 87.9 %. Furthermore, a pouch cell utilizing the prelithiated P-Si@rGO@C anode paired with LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM111) cathode delivers a high initial reversible capacity of 7.2 mAh and 76.8 % capacity retention after 100 cycles. This work provides insights into the application of commercial silicon-aluminum alloy powder in the anode of high-energy LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn-1-lysophosphatidylcholine underwent acyl migration due to structural instability. • Acyl migration rate was higher under acidic or alkaline conditions. • Nitrogen/vacuum increased yield of conjugated linoleic acid lysophosphatidylcholine. • The maximum yield was achieved when the vacuum pressure was 13.3 KPa. Sn -Glycerol-3 - phosphatidylcholine (GPC) was prepared by hydrolysis of phosphatidylcholine (PC) catalyzed by phospholipase A 1 (PLA 1). Nitrogen flow assisted the esterification of conjugated linoleic acid (CLA) and GPC to produce conjugated linoleic acid lysophosphatidylcholine (LPC − CLA). The effects of different reaction conditions on the PC conversion and acyl migration rates were investigated, and the acyl migration mechanism under acidic and alkaline conditions was studied. In addition, the optimum conditions for the esterification of CLA and GPC were selected. The optimal condition for the hydrolysis of PC was an enzyme loading of 5 %, pH of 5, reaction temperature of 50 ℃, and reaction time of 3 h. The results also showed that the maximum esterification rate reached 82.37 % at an enzyme loading of 15 %, CLA/GPC molar ratio of 50:1, and vacuum pressure of 13.3 kPa. This study not only improved the bioavailability of PC but also effectively increased the content of LPC − CLA. [ABSTRACT FROM AUTHOR]

• Hemp seeds were pretreated with a combination of ultrasound and ethanol. • The degradation rate of Δ9-THC was 92.14 % at ultrasonic power of 200 W for 30 min. • After optimizing the extraction conditions, the oil recovery rate reached 88.38%. • The Δ9-THC in the oil sample was 9.58 mg/kg. In this study, ultrasonic-ethanol pretreatment combined with AEE was developed for oil extraction from hemp seeds. The oil yield reached a maximum of 23.32 % at 200 W ultrasonic power and 30 min ultrasonic time, at this point, the degradation rate of Δ9-THC was 83.11 %. By determining the composition of hemp seed before and after pretreatment, it was shown that ultrasonic-ethanol pretreatment reduced the protein content of the raw material. An enzyme mixture consisting of pectinase and hemicellulase (1/1/1, w/w/w) was experimentally determined to be used, and the AEE extraction conditions were optimized using the Plackett-Burman design and the Box-Behnken. The optimal conditions were determined to be pH 5, total enzyme activity of 37,800 U/g, liquid–solid ratio of 10.4 mL/g, enzyme digestion temperature of 32 °C, enzymatic time of 189 min, and oil recovery of 88.38 %. The results of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) showed that the emulsion formed during ultrasonic ethanol pretreatment was not uniformly distributed, and the droplets appeared to be aggregated; and the irregular pores of hemp seed increased after pretreatment. The contents of Δ9-THC and CBN in the extracted oil samples were 9.58 mg/kg and 52.45 mg/kg, respectively. Compared with the oil extracted by Soxhlet extraction (SE), the oil extracted by this experimental method was of better quality and similar in fatty acid composition. [ABSTRACT FROM AUTHOR]

Although the fully grouted tension anchorage system (T-anchorage system) has been widely used in the field of anchoring of earthen heritage sites, it has always suffered from the failure of the bolt–slurry interface debonding and the strong attenuation of the shear stress of the bolt–slurry interface along the embedment length. In this article, a new type of fully grouted tension–compression composite anchorage system (TC-anchorage system) is proposed, which is made up of a pressure bearing system with the same diameter of the anchor hole at the end of the tension bolt. The in situ anchorage, pull-out test and interfacial stress–strain monitoring were carried out for the T-anchorage systems and the TC-anchorage systems. This was based on the preliminary analysis and comparison of the structure and working mechanism of the two anchorage systems. The test results show that: the average ultimate load of the TC-anchorage system is about 40% higher than that of the T-anchorage system. TC-anchorage systems have the characteristics of small elastic deformation and large plastic deformation. The strain at the bolt–slurry interface varies progressively along the embedded length with the increase of load in a positive skewness–bimodal–negative skewness curve. The working mechanism of TC-anchorage systems includes three progressive stages: bolt–slurry interface debonding, conical slurry formation and slurry extrusion. The research conclusion provides a reference for the application of TC-anchorage systems in the protection and reinforcement of earthen heritage sites. [ABSTRACT FROM AUTHOR]

Identifying whether a pentatricopeptide repeat (PPR) exists in an amino acid is a significant task in the field of bioinformatics. To address this problem, an identification method that combines an optimal feature set selection framework and machine learning algorithms is proposed to recognize the PPR coding genes and proteins in the sequence of amino acid. The original 188-dimensional (D) features are obtained using a feature extraction method, which is successively optimised through a covariance analysis, max-relevant-max-distance processing, and principal component analysis to reduce it to an optimal feature set that has fewer but more expressive features. Four machine learning methods are then used to serve as the classifiers for the identification task. The final number of feature data dimensions is reduced from 188 to only 10, and according to the experimental results from support vector machine methods, the loss of the AUC and the F 1 values are only 3.26% and 10.1%, respectively. Moreover, after applying the J48, random forest, and naïve Bayes methods as classifiers, it was also found that the optimal feature set with 10 dimensions has an almost equivalent performance for a 10-fold validation test. Identifying whether a pentatricopeptide repeat (PPR) exists in an amino acid is a significant task in the field of bioinformatics. To address this problem, an identification method that combines an optimal feature set selection framework and machine learning algorithms is proposed to recognise the PPR coding genes and proteins in the sequence of an amino acid. The original 188-dimensional (D) features are obtained using a feature extraction method, which is successively optimised through a covariance analysis, max-relevant-max-distance processing, and a principal component analysis to reduce it to an optimal feature set that has fewer but more expressive features. Four machine learning methods are then used to serve as the classifiers for the identification task. The final number of feature data dimensions is reduced from 188 to only 10, and according to the experimental results from support vector machine methods, the loss of the AUC and F 1 the value are only 3.26% and 10.1%, respectively. Moreover, after applying the J48, random forest, and naïve Bayes methods as classifiers, it was also found that the optimal feature set with 10 dimensions has an almost equivalent performance for a 10-fold validation test Image, graphical abstract [ABSTRACT FROM AUTHOR]

In the field of oil refining, the presence of excessive residual phosphorus in crude oil can significantly impact its quality, thereby emphasizing the necessity for compact and convenient testing equipment. This study primarily focuses on developing of self-powered biosensor (SPB) using immobilizing Choline Oxidase with a photoactive ternary nanocomposite complex (CHOx-BiOI-rGO-Fe 3 O 4 NPs-ITO) as the anode and utilizing a Pt electrode as the cathode. The successful preparation of the ternary composite photoelectrode for the anode was confirmed through a range of characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), N 2 absorption/desorption, Dynamic light scattering (DLS), and Ultraviolet–visible diffuse reflection spectrometer (UV–vis DRS). The electrochemical and photoelectrochemical properties were assessed using an electrochemical workstation, revealing a significant enhancement photoelectrical responsiveness attributed to the formation of heterojunction structures. The SPB exhibited a remarkable linear relationship between the instantaneous photocurrent and phosphatidylcholine (PC) concentration, with a regression equation of I (μA) = 39.62071C (mM) + 3.47271. The linear range covered a concentration range of 0.01–10 mM, and the detection limit (S/N = 3) was determined to be 0.008 mM. It demonstrated excellent reproducibility and storage stability, positioning it a promising alternative to High-performance liquid chromatography (HPLC) for accurate quantification of PC content in rhodotorula glutinis oil. The standard recovery PC content ranged from 98.48% to 103.53%, with a relative standard deviation (RSD) ranging from 1.4% to 2.4%. This research presents a convenient and precise detection device that has the potential to address the issue of lagging detection in the oil refining process. [Display omitted] [ABSTRACT FROM AUTHOR]

The fabricated VS 4 /Ni 3 S 2 /NF NBs was prepared by self-templated strategy, with exposed abundant hetero-interfaces and high active disulfide (S 2 2-) sites. The density functional theory revealed the reversible conversion catalysis mechanism of bridge S 2 2- during HER process, jointly promoting the HER performance. [Display omitted] • A novel VS 4 nanoparticle decorated Ni 3 S 2 nanobelt array was synthesized via one-step organic ligand-assisted solvothermal method. • The abundant disulfide (S 2 2-) moieties grafted on the hetero-interfaces of VS 4 /Ni 3 S 2 led to strong electronic interaction and promote the chemisorption of H-containing intermediates. • The density functional theory reveals the reversible conversion catalysis mechanism about disulfide (S 2 2-) sites during HER process. • The findings provide fresh insights for developing potential polysulfides as high-performance hydrogen-evolving electrocatalysts from water splitting. Elaborate and rational design of cost-effective and high-efficiency non-noble metal electrocatalysts for pushing forward the sustainable hydrogen fuel production is of great significance. Herein, a novel VS 4 nanoparticle decorated Ni 3 S 2 nanobelt array in-situ grown on nickel foam (VS 4 /Ni 3 S 2 /NF NBs) was prepared by a self-templated synthesis strategy. Benefitting from the unique nanobelt array structure, abundant highly active bridge S 2 2- sites and strong electronic interaction between VS 4 and Ni 3 S 2 on the heterointerface, the integrated VS 4 /Ni 3 S 2 /NF NBs exhibited excellent electrocatalytic hydrogen evolution activity and robust stability. The density functional theory (DFT) further revealed the reversible conversion catalysis mechanism of bridging S 2 2- sites in VS 4 /Ni 3 S 2 /NF NBs during HER process. Notably, bidentate bridging S S bonds as the predominant catalytically active centers can spontaneously open once H adsorbed its surface, leading to the aggregation of negative charges on S atoms and thus facilitating the generation of H* intermediates, and spontaneously close when H* desorption is going to form H 2. Our work provides fresh insights for developing potential polysulfides as high-performance hydrogen-evolving electrocatalysts for prospective clean energy production from water splitting. [ABSTRACT FROM AUTHOR]

A turn-on two-photon fluorescent probe HCA-Green for hypochlorous acid (HOCl) was synthesized using 4-methylamino-1,8-naphthalimide (MNA) as a two-photon fluorophore and p-hydroxyaniline as a leaving-recognition domain. Both the probe and the fluorophore were investigated under one- and two-photon excitation modes. The fluorescence intensity of the probe was enhanced by ∼229-fold and ∼193-fold under one-photon and two-photon excitation, respectively, after reacting with HOCl. A maximal two-photon action cross-section of 50 GM was obtained under excitation at 810 nm. The probe exhibited high sensitivity with a detection limit of 42.3 nM, as well as high selectivity, low cytotoxicity, and good photostability. Two-photon microscopy (TPM) was conducted to visualize HOCl levels in living cells and tissues. The production of endogenous HOCl induced by lipopolysaccharide-mediated inflammation was successfully monitored with this probe. [ABSTRACT FROM AUTHOR]

Abstract The Basel Accord requires commercial banks to meet a capital requirement for operational risk. Therefore, a reliable operational risk measurement is of great significance for financial institutions. In this paper, based on the framework of LDA, we propose a more appropriate model (Double Correlation model) in correlation structure construction, which considers both frequency correlation and mean severity correlation simultaneously. On this basis, annual loss scenarios for each risk cell are restored and VaR is also estimated by Monte Carlo simulation. Empirical study adopts the data of Chinese commercial banks disclosed to the public and contains the comparison of double correlation model and the other four correlation models. The result indicates that the VaR estimated by the double correlation model is significantly lower than that upon the assumption of comonotonicity, proving the existence of risk diversification. Meanwhile, the VaR estimated by double correlation model is significantly lower than that of the other two correlation models when confidence level is lower than 99% but the relationships between them will reverse if the confidence level rises to more than 99%. Highlights • We propose a double correlation model in operational risk modeling. • The model contains both frequency correlation and severity correlation. • We replace severity with mean severity in severity correlation construction. • We compare VaRs calculated by the double correlation model and other four models. [ABSTRACT FROM AUTHOR]

[Display omitted] • The industrial solid waste silicon powder is used as low-cost anode material. • Porous composites are constructed by a scalable, facile, and eco-friendly method. • C@void/Si-G anode exhibits excellent reversible capacity and cycling capability. • The synergistic effect of carbon and porous space produces excellent properties. Silicon is a potential anode material for Li battery due to its high theoretical specific capacity (4200 mAh g−1). However, Si is hampered for practical application in Li-battery due to its enormous volume alternation causing instability. Herein, we demonstrated a novel carbon-coated porous structure (C@void/Si-G) synthesized by uniformly wrapping Si into pitch pyrolytic carbon shells and then in-situ removing the sodium chloride template can overcome the bottleneck. It is worth noting that our process for C@void/Si-G also offers a simple route for cost down and mass production of anode material. The C@void/Si-G anodes exhibit an excellent capacity of 1082.7 mAh g−1 at 0.2 C after 200 cycles. Furthermore, it holds a high capacity retention of 81.9 % after 500 cycles at 0.5 C. We found that C@void/Si-G composite only rises about 41% volumetric expansion during 500 operation cycles. This can effectively avoid direct contact between silicon and electrolyte to form a stable solid electrolyte interphase (SEI) film. Especially, practical application of the C@void/Si-G anode is demonstrated in a full cell pairing with LiNi 0.3 Co 0.3 Mn 0.3 O 2 cathode. The full cell presents great cycle retention of 90.1 % at 0.2 C after 100 cycles and a high energy density (446 Wh kg−1). [ABSTRACT FROM AUTHOR]

Deep neural network-based object detectors are vulnerable to adversarial examples. Among existing works to fool object detectors, the camouflage-based method is more often adopted due to its adaptation to multi-view scenarios and non-planar objects. However, most of them can still be easily observed by human eyes, which limits their application in the real world. To fool human eyes and object detectors simultaneously, we propose a differential evolution based dual adversarial camouflage method. Specifically, we try to obtain the camouflage texture by the two-stage training, which can be wrapped over the surface of the object. In the first stage, we optimize the global texture to minimize the discrepancy between the rendered object and the scene background, making human eyes difficult to distinguish. In the second stage, we design three loss functions to optimize the local texture, which is selected from the global texture, making object detectors ineffective. In addition, we introduce the differential evolution algorithm to search for the near-optimal areas of the object to attack, improving the adversarial performance under certain attack area limitations. Experimental results show that our proposed method can obtain a good trade-off between fooling human eyes and object detectors under multiple specific scenes and objects. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the seismic behavior and failure mechanism of novel type of blind bolted concrete-filled steel tubular (CFST) composite frames under seismic loading. The composite frames are composed of square or circular CFST columns and steel-concrete composite beams with steel-bars truss deck (SBTD); the steel beams and the CFST columns are assembled by blind bolts and end plates. The failure modes, hysteretic behavior, strength and rigidity degradation, ductility and energy-dissipating performance of all specimens were analyzed and discussed. The influence of composite action of the floor slab on the performance of blind bolted CFST composite frames were also explored under seismic loading. The experimental results showed that the blind bolted CFST composite frames with the SBTD concrete slabs exhibited good hysteretic behavior, large ductility and high energy dissipation. The stiffness and strength of the frame increased greatly with the presence of the SBTD concrete slab. These test studies could promote the engineering design and application of the blind bolted CFST composite frames. [ABSTRACT FROM AUTHOR]

In this paper, an improved slope-based method (ISBM) based on empirical mode decomposition (EMD) and feed-forward neural network (FNN) method, namely, the EMD-ISBM-FNN method is introduced to decompose and forecast the crude oil prices. Firstly, the ISBM-based EMD method is used to decompose the time series of Brent crude oil prices into several IMFs (intrinsic mode functions) and residuals r n (t). Then IMFs and residuals r n (t) are inputted into the FNN model as input layer neurons, which are trained and integrated by the FNN model to study the relationship between the output values of the FNN and actual values. In order to verify the forecasting results of the EMD-ISBM-FNN model, two research frameworks and three strategies are designed, and the EMD-FNN model and the FNN model as the benchmark models are constructed to compare their forecasting results. The research shows that the EMD-ISBM-FNN model proposed in this paper has the best forecasting effect under the three strategies, and the research framework of this paper is better than the previous scholars' research frameworks, too. • A novel data envelope method (ISBM) is proposed based on EMD algorithm and neural network. • The Fixed window iterative strategy created the best results in the three strategies. • A new research plan is designed by the EMD-ISBM-FNN model. [ABSTRACT FROM AUTHOR]

BACKGROUND Isotopic discrimination, dietary composition and feeding regime determine the carbon and nitrogen stable isotope ratios of animals. Accordingly, measurement of the stable isotope ratios of carbon and nitrogen can be a potential method to identify patterns of pork production. RESULTS In the current study, we investigated the carbon and nitrogen isotopic ratio in pork from organic and conventional systems. The average carbon and nitrogen isotope ratios for various organic tissues, including hair, blood and defatted meat, were higher than those of conventionally raised ones. The discriminant analysis results based on the combination of carbon and nitrogen isotopic ratios in defatted meat reached a 100% correct classification. Furthermore, the variation in carbon and nitrogen stable isotope ratios of retail organic and conventional pork has been studied over 1 year. The results suggested that organic pork had a higher δ13C value than that of the conventional pork in all but three fortnights. Grouping of the δ15N data showed that the δ15N value in organic pork was higher than that of the conventional one throughout the whole year. CONCLUSION The method established in the present study provides a potential detection that can be highly valuable to prevent fraudulent labelling of organic pork. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Karst rocky desertification (KRD) has become one of the most serious ecological and environmental problems in karst areas. At present, mapping KRD with a high accuracy and on a large scale is still a difficult problem in the control of KRD. In this study, a random forest (RF) based on maximum information coefficient and correlation coefficient feature selection is proposed to predict KRD. Nine predictors stood out as feature factors to estimate KRD. Rock exposure was the most important predictor, followed by fractional vegetation cover for the prediction of KRD processes. The kappa and classification accuracy indexes were to evaluate the performance of the model. We recorded overall accuracy rate and kappa index values of 94.7% and 0.92 for the testing datasets respectively. The RF model was then used to predict the KRD in 2001, 2011, 2016, and 2020, and it was found that the KRD in the study area has exhibited a positive trend of improvement. Therefore, the use of multisource remote sensing data combined with the RF model can obtain better prediction results of KRD, thereby providing a new idea for large-scale estimation of the KRD in peak-cluster depression. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 3-dimensional structure comprised of silicon nanoparticles assembled on an nitrogen-doped carbon foam with MXene as the cover layer (MXene@SiNPs@NC foam) is demonstrated. • The MXene layer protects the silicon nanoparticles from directly contacting the electrolyte. • The nitrogen-doped carbon foam and MXene are used as the conductive frame and covering layer, providing effective channels for electron transport/ion diffusion. • The substantial void spaces between the MXene layer and the nitrogen-doped carbon foam skeleton can accommodate the significant silicon nanoparticles volume change during lithiation/delithiation. • The self-standing and binder-free anode was used without a metal current collector. Silicon (Si) is one of the most promising anode materials for lithium-ion batteries (LIBs) because of its high specific capacity. However, the poor cycling stability results from huge volume fluctuation and low intrinsic conductivity, which greatly hinders Si-based anodes development. Herein, we construct a three-dimensional structure comprised of Silicon nanoparticles (SiNPs) anchored on a nitrogen -doped carbon (NC) foam with a covered MXene layer (MXene@SiNPs@NC foam), which acts as a self-standing Si-based anode for high performance LIBs. The design of NC foam as the conductive frame and MXene as the covering layer provides effective channels for electron transport/ion diffusion, and simultaneously allows the anode to adapt to the drastic Si volume change during lithiation/delithiation. The self-standing MXene@SiNPs@NC foam electrode delivers a high specific capacity (1658 mAh g−1 after 100 cycles at 0.1C) and a steady cycling capacity (857 mAh g−1 after 500 cycles at 0.5C). Moreover, a full-cell constructed using MXene@SiNPs@NC foam //NCM 111 exhibits a high gravimetric energy density (433 Wh kg−1). This MXene@SiNPs@NC foam anode with good electrochemical performance renders as a promising candidate for broad LIBs applications. [ABSTRACT FROM AUTHOR]

Currently, with the rise of the photovoltaic industry, how to effectively treat waste silicon powder from an environmentally friendly and economic point of view becomes significant. We reported a simple method to prepare the "core-shell" structure of silicon/carbon nanotubes/carbon (Si/CNTs/C) composite by ball-milling using waste silicon powder. Specifically, The synergistic effect of CNTs and amorphous carbon matrix is beneficial to improving the transmission rate of Li-ions and electrons, and facilitating the reaction kinetics of Li-ions in the process of lithiation/de-lithiation. Meanwhile, the carbon coating layer reduces the direct contact between silicon and the electrolyte, which greatly alleviates the volume expansion of silicon in cycling. With these merits, Si/CNTs/C anode shows high rate performance and outstanding cycling stability up to 300 cycles at 0.2C. Furthermore, full cells assembled with pre-lithiated Si/CNTs/C anodes and commercial NCM811 cathodes deliver considerable initial coulombic efficiency (84.4%) and high energy density (502 Wh kg−1). Si/CNTs/C composites prepared by ball-milling show excellent long-cycle stability and rate performance. [Display omitted] • Industrial waste silicon is used to prepare silicon-based anodes. • Two-step ball milling method to prepare Si/CNTs/C composite. • A solution-based chemical prelithiation method is proposed. • Si/CNTs/C anode exhibits excellent long-cycle stability and good rate performance. • A full cell shows an improved ICE (84.4%) and a higher energy density (502 Wh kg−1). [ABSTRACT FROM AUTHOR]

The optimal allocation of educational resources has been a hot issue, and exploring the accessibility of educational facilities in poor mountainous areas helps to reasonably plan the layout of educational facilities and promote the balanced development of education. Taking the rocky desertification area in Yunnan, Guangxi, and Guizhou (YGGRD) as the study area, based on the POI data of educational facilities in the YGGRD in 2000, 2010 and 2019, this study explored the evolution of the accessibility of educational facilities in the YGGRD through raster accessibility. And the influencing factors were analyzed by the ordinary least square method (OLS) and geographically weighted regression model (GWR), and evaluated the model through cross validation. The results show that the overall accessibility of educational facilities improved significantly from 2000 to 2019. Educational facilities mainly have good accessibility and average accessibility. Poor accessibility areas are concentrated in the interprovincial border regions, and the boundary effect is significant. County accessibility, population density and rural per capita disposable income have a great impact on the accessibility of educational facilities in the YGGRD. It is suggested to strengthen the construction of educational facilities in the interprovincial border regions, relocate and integrate villages, and improve the education quality of township schools to improve the supply of rural educational resources. [ABSTRACT FROM AUTHOR]