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Recently, boron (B)/nitrogen (N)‐embedded polycyclic aromatic hydrocarbons (PAHs), characterized by multiple resonances (MR), have attracted significant attention owing to their remarkable features of efficient narrowband emissions with small full width at half maxima (FWHMs). However, developing ultra‐narrowband pure‐green emitters that comply with the Broadcast Service Television 2020 (BT2020) standard remains challenging. Precise regulation of the MR distribution regions allows simultaneously achieving the emission maximum, FWHM value, and spectral shape that satisfy the BT2020 standard. The proof‐of‐concept molecule TPABO‐DICz exhibited ultrapure green emission with a dominant peak at 515 nm, an extremely small FWHM of 17 nm, and Commission Internationale de l′Eclairage (CIE) coordinates of (0.17, 0.76). The corresponding bottom‐emitting organic light‐emitting diode (OLED) exhibited a remarkably high CIEy value (0.74) and maximum external quantum efficiency (25.8 %). Notably, the top‐emitting OLED achieved nearly BT2020 green color (CIE: 0.14, 0.79) and exhibited a state‐of‐the‐art maximum current efficiency of 226.4 cd A−1, thus fully confirming the effectiveness of the above strategy. [ABSTRACT FROM AUTHOR]

Recently, boron (B)/nitrogen (N)‐embedded polycyclic aromatic hydrocarbons (PAHs), characterized by multiple resonances (MR), have attracted significant attention owing to their remarkable features of efficient narrowband emissions with small full width at half maxima (FWHMs). However, developing ultra‐narrowband pure‐green emitters that comply with the Broadcast Service Television 2020 (BT2020) standard remains challenging. Precise regulation of the MR distribution regions allows simultaneously achieving the emission maximum, FWHM value, and spectral shape that satisfy the BT2020 standard. The proof‐of‐concept molecule TPABO‐DICz exhibited ultrapure green emission with a dominant peak at 515 nm, an extremely small FWHM of 17 nm, and Commission Internationale de l′Eclairage (CIE) coordinates of (0.17, 0.76). The corresponding bottom‐emitting organic light‐emitting diode (OLED) exhibited a remarkably high CIEy value (0.74) and maximum external quantum efficiency (25.8 %). Notably, the top‐emitting OLED achieved nearly BT2020 green color (CIE: 0.14, 0.79) and exhibited a state‐of‐the‐art maximum current efficiency of 226.4 cd A−1, thus fully confirming the effectiveness of the above strategy. [ABSTRACT FROM AUTHOR]

We report the influences of oxygen interstitials and magnetisms on phase stability and structural transformation of CoCrFeNi high-entropy alloy (HEA) from first-principles calculations. It is found the formation of oxygen interstitials is energetically favourable to occur in face-centred cubic (FCC) CoCrFeNiOx HEA as compared with that in hexagonal close-packed (HCP) one, and at those octahedral sites neighbouring with more Cr or less Ni. Meanwhile, it is determined the HEA prefers FCC over HCP phases when the oxygen concentration exceeds 4.2 and 5.1 at.% with and without considering its magnetisms, respectively. The HCP-to-FCC structural transformation in CoCrFeNiOx HEA could be magnetically driven, accompanied by the significant changes in the atomic magnetic moments in the HEA, particularly with an oxygen interstitial concentration larger than 2.7 at.%. Furthermore, the HCP-to-FCC transformation under hydrostatic pressure in CoCrFeNi and CoCrFeNiOx HEAs is investigated from generalised stacking fault energies, and it is revealed that the synergy effects of oxygen interstitials and magnetisms could facilitate the transformation in CoCrFeNiOx HEA. The coupled interstitials-induced and magnetically driven structural transformation paves a new avenue for the application of HEAs. [ABSTRACT FROM AUTHOR]

The Bayesian inference is widely used in many scientific and engineering problems, especially in the linear inverse problems in infinite-dimensional setting where the unknowns are functions. In such problems, choosing an appropriate prior distribution is an important task. Especially when the function to infer has much detail information, such as many sharp jumps, corners, and the discontinuous and nonsmooth oscillation, the so-called total variation-Gaussian (TG) prior is proposed in function space to address it. However, the TG prior is easy to lead the blocky (staircase) effect in numerical results. In this work, we present a fractional order-TG (FTG) hybrid prior to deal with such problems, where the fractional order total variation (FTV) term is used to capture the detail information of the unknowns and simultaneously uses the Gaussian measure to ensure that it results in a well-defined posterior measure. For the numerical implementations of linear inverse problems in function spaces, we also propose an efficient independence sampler based on a transport map, which uses a proposal distribution derived from a diagonal map, and the acceptance probability associated to the proposal is independent of discretization dimensionality. And in order to take full advantage of the transport map, the hierarchical Bayesian framework is applied to flexibly determine the regularization parameter. Finally we provide some numerical examples to demonstrate the performance of the FTG prior and the efficiency and robustness of the proposed independence sampler method. [ABSTRACT FROM AUTHOR]

In this work, we present a high‐reliability gate driver on array (GOA) for a 10.7‐in. HD (1,280 × RGB × 720) TFT‐LCD panel, featuring an alternatively double‐sided noise‐eliminating function. The gate driver circuit is designed with 12‐phase clock signals that exhibit 75% signal overlapping, threshold voltage recovering, and double‐sided driving schemes. The double‐sided driving scheme reduces the number of mental wires and TFTs in the gate driver circuit, resulting in a smaller layout area for GOA. By utilizing dual levels of voltage, we implemented a negative gate bias method to mitigate threshold voltage shifts for the noise‐eliminating and driving TFTs. This prevents the noises from clock signals effectively. The reliability test of the proposed GOA with 720 stages passed a strict testing condition (90°C and −40°C) for simulation and exhibited good performance over 800 hours at 90°C for measurement. [ABSTRACT FROM AUTHOR]

Developing new organic reactions with excellent atom economy and high selectivity is significant and urgent. Herein, by ingeniously regulating the reaction conditions, highly selective transformations of propargylamines have been successfully implemented. The palladium-catalyzed cyclization of propargylamines generates a series of functionalized quinoline heterocycles, while the base-promoted isomerization of propargylamines affords diverse 1-azadienes. Both reactions have good functional group tolerance, mild conditions, excellent atom economy and high yields of up to 93%. More importantly, these quinoline heterocycles and 1-azadienes could be flexibly transformed into valuable compounds, illustrating the validity and practicability of the propargylamine-based highly selective reactions. [ABSTRACT FROM AUTHOR]

Objective To understand the urinary fluoride level and changes in bone biochemical metabolism indexes among workers exposed to ammonium bifluoride and to explore bone metabolism biomarkers in ammonium bifluoride -exposed workers. Methods Totally 74 workers occupationally exposed to ammonium bifluoride in a semiconductor and liquid crystal panel production enterprise (as an exposed group), as well as 70 workers in a nearby electronic factory (as a control group), were studied. The urinary fluoride, serum osteocalcin, serum alkaline phosphatase, and urine hydroxyproline were measured, and the differences between these two groups were compared. Results The airborne concentrations of hydrogen ammonium bifluoride (calculated as hydrogen fluoride) in the workplaces of the studied plant varied from non-detectable (lower than 0.014) to 0.021 mg/m3, which were lower than the national occupational exposure limit. Seven workers in the exposure group had excessive fluoride values in their pre-shift urine samples, with an excessive rate of 9.45%. There was a positive correlation between the urinary fluoride values of workers in the exposure group and the airborne concentration of hydrogen fluoride (r = 0.332, P < 0.05). The urinary fluoride mass concentration of workers in the exposure group [(0.69 ± 0.77) mg/L] was higher than that of the control group [(0.47 ± 0.17) mg/L], and the difference was statistically significant (P < 0.05). The serum osteocalcin concentration of workers in the exposure group [(15.07 ± 3.68) ng/mL] was lower than that of the control group [(16.51 ± 4.51) ng/mL], and the difference was statistically significant (P < 0.05). There was no significant difference between the serum alkaline phosphatase concentration [(76.99 ± 14.99) U/L] of workers in the exposure group and that of the control group [(75.03 ± 22.35) U/L] (P > 0.05). The urine hydroxyproline concentration of workers in the exposure group [(1 134.01 ± 145.34) μmol/L] was higher than that of the control group [(721.30 ± 138.31) μmol/L], and the difference was statistically significant (P < 0.01). If the workers were grouped according to their urinary fluoride level, those with higher urinary fluoride values than 1.0 mg/L had higher urinary hydroxyproline values than those of those with lower urinary fluoride values (> 0.5 - 1.0 mg/L and > 0 - 0.5 mg/L) (P < 0.05). Conclusions Urinary fluoride and urine hydroxyproline may be sensitive biomarkers of bone metabolism in workers exposed to ammonium bifluoride. [ABSTRACT FROM AUTHOR]

In this article, we study uniqueness and nonuniqueness for internal potential reconstruction from one boundary measurement in quantum fields that is related to the steady state Schrödinger equation. It is an extension of our recent work [On uniqueness and nonuniqueness for internal potential reconstruction in quantum fields from one measurement, J. Comput. Appl. Math.381 (2021), Paper No. 113029]. Based on the theory of the ND map and modified Bessel function, the uniqueness theorem of the inverse problem in two-dimensional and three-dimensional core-shell structure is established, respectively. When different internal potential and shape are considered, the nonuniqueness results are also proved. We then present some numerical examples to illustrate our theoretical results. [ABSTRACT FROM AUTHOR]

Concurrently achieving high energy storage density (ESD) and efficiency has always been a big challenge for electrostatic energy storage capacitors. In this study, we successfully fabricate high-performance energy storage capacitors by using antiferroelectric (AFE) Al-doped Hf0.25Zr0.75O2 (HfZrO:Al) dielectrics together with an ultrathin (1 nm) Hf0.5Zr0.5O2 underlying layer. By optimizing the Al concentration in the AFE layer with the help of accurate controllability of the atomic layer deposition technique, an ultrahigh ESD of 81.4 J cm−3 and a perfect energy storage efficiency (ESE) of 82.9% are simultaneously achieved for the first time in the case of the Al/(Hf + Zr) ratio of 1/16. Meanwhile, both the ESD and ESE exhibit excellent electric field cycling endurance within 109 cycles under 5~5.5 MV cm−1, and robust thermal stability up to 200 °C. Thus, the fabricated capacitor is very promising for on-chip energy storage applications due to favorable integratability with the standard complementary metal–oxide–semiconductor (CMOS) process. [ABSTRACT FROM AUTHOR]

2D materials that possess multifunctional properties are of great interest for applications in semiconducting devices. Herein, a series of novel Janus XYP2 (X/Y = Si, Ge, Sn, and Pb; X ≠ Y) monolayers with good stability, electronic, mechanical, piezoelectric properties, as well as ferromagnetic properties are predicted based on density functional theory. They are all indirect‐bandgap semiconductors with bandgaps varying from 0.56 to 2.18 eV. The monolayers exhibit in‐plane and out‐of‐plane piezoelectricity with large piezoelectric coefficients, suggesting that they are promising piezoelectric materials for nanoelectromechanical systems. In SiGeP2, GeSnP2, and SnPbP2 monolayers, hole doping is found to be an effective approach in inducing or tuning different ferromagnetic states resulting from electronic instability as reflected by van Hove singularity of band structures in the 2D systems. The results suggest that Janus XYP2 monolayers can be promising 2D materials for applications in nanoelectronic, spintronic, and nanoelectromechanical devices. [ABSTRACT FROM AUTHOR]

Carbon nanospheres (CNSs) have attracted great interest in energy conversion and storage technologies due to their excellent chemical and thermal stability, high electrical conductivity and controllable size structure characteristics. In order to further improve the energy storage properties, many efforts have been made to design suitable nanocarbon spherical materials to improve electrochemical performance. In this overview, we summarize the recent research progress on CNSs, mainly focusing on the synthesis methods and their application as high-performance electrode materials in rechargeable batteries. As for the synthesis methods, hard template methods, soft template methods, the extension of the Stöber method, hydrothermal carbonization, aerosol-assisted synthesis are described in detail. In addition, the use of CNSs as electrodes in energy storage devices (mainly concentrated on lithium-ion batteries (LIBs)), sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) are also discussed in detail in this article. Finally, some perspectives on the future research and development of CNSs are provided. [ABSTRACT FROM AUTHOR]

Accurate classification of tree species is essential for forest resource monitoring, management, and conservation. Based on the classification of tree species, the biomass model at the individual-tree scale of each tree species can be accurately estimated, which can improve the estimation efficiency of individual-tree biomass. In this study, we first extracted four categories of indicators: canopy height model, spectral features, vegetation indices, and texture features from airborne-laser-scanning (ALS) data and hyperspectral data. We used these features as inputs to the random forest algorithm and screened out the optimal variable combination for tree-species classification, with an overall accuracy of 84.4% (kappa coefficient = 0.794). Then, we used ALS data to perform tree segmentation in forest plots to extract tree height, crown size, crown projected area, and crown volume. According to multivariate nonlinear fitting, the parameters of the individual-tree structure were introduced into the constant allometric ratio (CAR) biomass model to establish the biomass models of three tree species: Douglas fir, Red alder, and Bigleaf maple. The results showed that the model-fitting effects were improved after introducing the crown parameters. In addition, we also found that better tree segmentation results led to more accurate structural parameters. [ABSTRACT FROM AUTHOR]

Control laws can be constructed in systems design by introducing parameters to obtain good system performance or robustness. Cai et al., in their paper 'Design of LPV controller for morphing aircraft using inexact scheduling parameters', establish a linear parameter-varying model for a morphing aircraft by Jacobian linearization. With such a model, Cai et al. investigate the design problem of gain-scheduled output-feedback controllers by using inexact scheduling parameters for morphing aircraft during the wing transition process. [Extracted from the article]

Circularly polarized organic light‐emitting diodes (CP‐OLEDs) are ideal candidates to explore novel applications such as 3D displays, optical storage, and quantum computing. However, the low dissymmetry (g) factor of most chiral organic materials remains as a major challenge for practical applications. In this work, a helical stacking assembly of orderly silicon nanowires (hs‐SiNWs) into a flexible multilayer 3D superstructure is demonstrated to accomplish a strong chiroptical activity. These orderly SiNWs are batch‐fabricated via a low temperature in‐plane solid–liquid–solid growth mechanism, with precisely‐controlled spatial arrangement and mean diameter and length of Dnw = 126 ± 24 nm and Lnw > 100 µm, respectively. To construct such helically‐stacked superstructure, the SiNW arrays are transferred and stacked upon transparent glass or flexible polymer substrates, with incremental rotational angle for each layer, which can strongly augment the circularly polarized electroluminescence (CPEL) from conventional CP‐OLEDs. Strikingly, the dissymmetry factor increases with more stacking layer up to g = ±0.17, which is more than 40 times of magnitude higher than that of the original CPEL, among the highest ones reported for CP‐OLEDs. These results indicate a promising helical‐stacking avenue to boost the chiroptical performance of various CP‐OLEDs for scalable and flexible chiroptical applications. [ABSTRACT FROM AUTHOR]

Detecting damages, especially micro-damages, early and accurately is crucial to the safety of drilling risers. This study presents a high-precision model for detecting micro-damages in drilling risers based on modal information using Machine Learning (ML) algorithms. The under-sampling technique is applied to ensure a balanced distribution of data. The modal information data set is used to analyze three machine learning models: Random Forest (RF), Extreme Learning Machine (ELM), and Back Propagation Neural Network (BPNN). The study investigates their applicability and interpretability in damage identification. SHapley Additive exPlanations (SHAP) analysis is utilized to unveil the decision-making process behind the models. The findings indicate that each model offers unique advantages, with the RF and BPNN models achieving a superior performance in terms of generalization ability. The study finally conducts feature optimization on the BPNN model based on SHAP values and develops a BPNN-4 model with enhanced stability and generalization capabilities. This research highlights the potential of applying interpretable ML techniques in structural health monitoring, offering a promising direction for future offshore engineering diagnostics. • Accuracy of damage identification in drilling risers is improved by using an interpretable feature optimization method. • The under-sampling method is employed to balance the data set and improve the efficiency of model training. • Three machine learning models, i.e., BPNN, ELM, and RF, are compared for damage identification of drilling risers. • Effectiveness of the machine learning algorithms is verified by combining statistical parameters and generalization analysis. [ABSTRACT FROM AUTHOR]

Models based on a parabolic equation (PE) can accurately predict sound propagation problems in range-dependent ocean waveguides. Consequently, this method has developed rapidly in recent years. Compared with normal mode theory, PE focuses on numerical calculation, which is difficult to use in the mode domain analysis of sound propagation, such as the calculation of mode phase velocity and group velocity. To broaden the capability of PE models in analyzing the underwater sound field, a wave mode calculation method based on PE is proposed in this study. Step-split Padé PE recursive matrix equations are combined to obtain a propagation matrix. Then, the eigenvalue decomposition technique is applied to the matrix to extract sound mode eigenvalues and eigenfunctions. Numerical experiments on some typical waveguides are performed to test the accuracy and flexibility of the new method. Discussions on different orders of Padé approximant demonstrate angle limitations in PE and the missing root problem is also discussed to prove the advantage of the new method. The PE mode method can be expanded in the future to solve smooth wave modes in ocean waveguides, including fluctuating boundaries and sound speed profiles. [ABSTRACT FROM AUTHOR]

Geochemical, geochronological, and Lu–Hf isotopic data for mafic–intermediate dykes on Robert Island, West Antarctica, are systematically investigated in order to decipher their petrogenesis and the genetic relationship between the South Shetland Islands and the north‐western Antarctic Peninsula. These dykes are enriched in large‐ion lithophile elements with significantly negative Nb and Ta anomalies, and low (Hf/Sm)N and (Nb/La)N and high Ba/La and Ba/Th ratios, with high εHf(t) values of +8.2 to +14.2. They were derived from partial melting of depleted mantle metasomatized by slab‐derived fluids. Precise ages of 55–54 Ma for the dykes confirm the occurrence of Early Eocene magmatism on Robert Island, corresponding to the final peak of subduction‐related magmatism. The available data suggest that Early Palaeogene (62–54 Ma) igneous rocks on the South Shetland Islands and the north‐western Antarctic Peninsula are products of contemporaneous and different lithofacies magmatism with precursors originating from depleted mantle in a magmatic arc setting. Furthermore, the Early Palaeogene igneous activities were most likely associated with slab rollback and extension in fore‐arc regions resulting from the decreasing convergence rate for the subduction of the Phoenix Plate beneath the Antarctic Plate at ~60 Ma. [ABSTRACT FROM AUTHOR]

[Display omitted] • A three-stage wavelength selection method is constructed by combining CC and SWR. • Wavelength selection results meet requirements of MLR modeling method. • The three-stage wavelength selection method exhibits certain superiority over other methods. The near-infrared spectral data is highly high dimensional and contains redundant information, it is necessary to identify the most representative characteristic wavelengths before modeling to improve model accuracy and reliability. At present, there are many methods for selecting the characteristic wavelengths of NIR spectroscopy, but the collinearity among wavelengths is still a main issue that leads to poor model effects. Therefore, this study proposes a three-stage wavelength selection algorithm (Stage III) to reduce redundancy in NIR spectral data and collinearity between wavelength variables, resulting in a simpler and more accurate predictive model. The research uses a public NIR data set of corn samples as its subject. Initially, the wavelengths with the higher correlation coefficients are chosen after calculating the relationship coefficients between every wavelength vector and the concentration vector. On this basis, the correlation coefficients between the vectors of each wavelength point are calculated, and those wavelength points with smaller correlation coefficients with other wavelength points are selected. Ultimately, the stepwise regression analysis selects the wavelengths that provide substantial value to the model as the variables for modeling, leading to the development of a multiple linear regression model. The results show that the model using the three-stage wavelength selection algorithm outperforms those using the full spectrum, Stages I and Stage II, and the coefficient of determination of the test set of the Stage III-MLR model achieved an accuracy of 0.9360. Instead of the successive projections algorithm (SPA), uninformative variable elimination (UVE), and competitive adaptive reweighted sampling (CARS), Stage III is better in the model prediction accuracy. Therefore, the three-stage wavelength selection algorithm is an effective wavelength selection algorithm that can effectively model NIR spectroscopy, reduce the collinearity between the wavelength variables, simplify the complexity of the model, and improve the prediction precision of the model. [ABSTRACT FROM AUTHOR]

In the experiment, butylacetate was used as the extraction solvent to optimize the extraction process of β-carotene. After concentration, crystallization and recrystallization, pure β-carotene with high content was prepared. The results showed that the optimal extraction conditions were extraction temperature 45 °C, two extraction time 1 h, ratio of liquid to material 10 mL/g for one extraction, ratio of liquid to material 7 mL/g for two extraction. Recrystallization of coarse and fine powder was carried out to obtain pure β-carotene product, whose content was 95%. The study indicates that the purified carotene obtained by the optimized extraction process has higher content, and the solvent used can be recycled and less pollution to the environment, which can be widely used in the application of feed additives. [ABSTRACT FROM AUTHOR]

To concurrently realize large electroluminescence dissymmetry factor and high device efficiency remains a formidable challenge in the development of circularly polarized organic light‐emitting diode (CP‐OLED). In this work, by introducing a famous chiral resource of R‐camphor, two green chiral iridium(III) isomers of Λ/Δ‐Ir‐(R‐camphor) containing dual stereogenic centers at iridium and ancillary ligand, are efficiently synthesized. Benefiting from their high phosphorescence quantum yields (≈93%) and obvious circularly polarized photoluminescence property with dissymmetry factors (|gPL|) in the 10−3 order of magnitude, the circularly polarized phosphorescent organic light‐emitting diodes using these chiral emitters show excellent performances with the maximum external quantum efficiency (EQEmax) of 30.6%, low efficiency roll‐off, and intense circularly polarized electroluminescence signal with dissymmetry factor (gEL) in the 10−4 order of magnitude. By the novel device engineering with semitransparent cathode, the resulting gEL values are significantly boosted by one order of magnitude, up to 7.70 × 10−3, which is the highest among the CP‐OLEDs with chiral iridium complexes. Noteworthy, the semitransparent devices deliver a record‐high EQEmax of 18.8% among the semitransparent OLEDs. The combination of novel chiral Ir(III) complexes and the semitransparent devices sheds light on the development of high performance CP‐OLEDs with simultaneously high efficiency and large dissymmetry factor. [ABSTRACT FROM AUTHOR]

In the paper, a variational Bayesian method is used to identify the reaction coefficient for space-time nonlocal diffusion equations using nonlocal averaged flux data. To show the posterior measure to be well-defined, we rigorously prove that the forward operator is continuous with respect to the unknown reaction field. Then, gradient-based prior information is proposed to explore oscillation features in the reaction coefficient. Moreover, the Bayesian inverse problem is shown to be well-posed in Hellinger distance. To accurately characterize the posterior density using uncorrelated samples, an efficient variational Bayesian method is used to estimate the reaction coefficient in the nonlocal models. A few numerical results are presented to illustrate the efficacy of the proposed approach and confirm some theoretic discoveries. [ABSTRACT FROM AUTHOR]

The purposes of this study was to determine the toxicological effect of repeated intravenous administration of Activin A/BMP-2 chimera (AB204) in beagle dogs for a long period of four weeks and evaluate two-week recovery. AB204 was administered at doses of 0.08, 0.16, or 0.32 mg/kg/day to three male and three female beagle dogs for 4 weeks as the experimental group. For the control group, sterile saline was administered to three male and three female beagle dogs. For the two-week recovery test, two male and two female beagle dogs were randomly selected from the control group and the 0.32 mg/kg/day administered experimental group. General symptoms, body weight, food consumption, ophthalmological examination, electrocardiogram, urinalysis, hematology and blood biochemistry, organ weights, autopsy, and histopathological examination were observed or conducted. No animals died. There was no significant difference in any parameter evaluated between the experimental group and the control group. Histopathological examination revealed compound inflammation at the administration site in both the experimental group and the control group. The inflammation disappeared during the two-week recovery. These results indicated that repetitive intravenous injection of AB204 in beagle dog for a long period of four weeks did not show any toxicity. Therefore, no observed adverse effects level (NOAEL) of AB204 was 0.32 mg/kg/day in big animal model. [ABSTRACT FROM AUTHOR]

This paper designs a robust output feedback controller for input-saturated systems with parametric uncertainties and external disturbances based on the parametric Riccati equation and the sliding mode observer. The stability of the closed-loop system is ensured by the designed controller. The main advantages of the approach proposed in this paper are as follows: (a) the designed sliding mode observer can estimate unknown external disturbances and parametric uncertainties; (b) the designed output feedback controller can increase the state convergence speed; and (c) the control gain can be obtained from the solution of the parametric Riccati equation. The simulation results for a spacecraft rendezvous system illustrate the feasibility of the designed controller. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reduce the dimensionality of the near-infrared spectral data using mRMR. • The mRMR can assist near-infrared models to perform effectively. • This approach is more stable and adaptable than UVE, CARS, and SPA. Near-infrared spectroscopy (NIRS) is a rapid, nondestructive analytical technique utilized in various fields. However, the NIR data, which consists of hundreds of dimensions, may exhibit considerable duplication in the spectrum information. This redundancy might impair modeling effectiveness. As a result, feature selection on the spectral data becomes critical. The Max-Relevance Min-Redundancy (mRMR) method stands out among the different feature selection techniques for dimensional reduction. The approach depends on mutual information (MI) between random variables as the basis for feature selection and is unaffected by modeling methods. However, it is necessary to clarify the benefits of the maximum correlation minimal redundancy algorithm in the context of near-infrared spectral feature selection, as well as its adaptability to various modeling methods. This research focuses on the NIR spectral dataset of maize germination rate, and the mRMR method is utilized to select spectral features. Based on the preceding foundation, we create models for Support Vector Regression, Gaussian Process Regression, Random Forest, and Neural Networks. The experimental findings demonstrate that, among the feature selection methods employed in this paper, the Max-Relevance Min-Redundancy algorithm outperforms others regarding the corn germination rate dataset. [ABSTRACT FROM AUTHOR]

This paper proposes a novel adaptive output observer method for the distributed output tracking control of heterogeneous systems. Unlike the existing adaptive distributed state observer, an output-based adaptive distributed output observer (OADOO) that only relies on the leader's output is proposed to estimate the leader's information. Meanwhile, an input-based triggering mechanism is exploited to avoid continuous interactions between agents, and between the leader and its neighboring agents, respectively. Then, a local controller is developed to achieve the output tracking control. In comparison with the existing results for the similar research problem, our results not only handle the tracking control subject to only relative output measurement, but also considerably lower the data exchange traffic and dimension among agents of the developed OADOO. [ABSTRACT FROM AUTHOR]

At present, cyclometalated iridium (Ir)(III) complexes are the most promising emitters for OLEDs. Contrary to well-developed Ir(III)-based red and green phosphorescent complexes, the efficient blue emitters are limited and the performances of blue OLEDs are still not satisfactory. Inspired by this, we designed two novel blue Ir(III) complexes employing 2-(2,4-difluoropyridyl)pyridine (dfpypy) and 2,6-difluoro-3-(pyridin-2-yl)benzonitrile (FCN) as the main ligands, respectively, and phenyl(pyridin-2-yl)phosphinate (ppp) as the ancillary ligand. The rational design of the molecular structure makes the two complexes achieve blue emission and possess good electron mobility simultaneously. The devices based on the Ir(III) phosphors exhibited good electroluminescence performances with low turn-on voltages, a peak current efficiency of 24.51 cd A−1, a maximum external quantum efficiency of 12.4%, a peak power efficiency of 21.99 lm W−1 and low efficiency roll-off. These results provide an effective strategy for the future molecular design of blue Ir(III) complexes with good electron transport property for OLEDs. [ABSTRACT FROM AUTHOR]

This paper investigates the inverse reaction coefficient problem for a time dependent nonlocal diffusion equation by utilizing the nonlocal flux measurement from an accessible part of region, which is a continuation and an extension of our recent work (Zheng and Ding 2020 Inverse Problems 36 035006). The uniqueness of inverse reaction coefficient problem is proved. The variational regularization method is proposed to overcome the ill-posedness of inverse problem, and an alternating iteration method is adopted to automatically select regularization parameters. Furthermore, we use Laplace approximation method to capture the statistics information of the solution. In particular, we prove the lower bound of confidence width is rigorously estimated to characterize the reliability of the method. Finally, numerical results indicate that the proposed method could yield an accurate estimate and efficient uncertainty quantification of the solution. [ABSTRACT FROM AUTHOR]

This article investigates the fully distributed observer-based adaptive fault-tolerant synchronization problem (SP) of multiagent systems with event-triggered control mechanisms. First, a nonlinear and discontinuous adaptive observer-based event-triggered fault-tolerant controller is proposed for each agent to overcome the occurrence of unknown faults and unmeasurable full states of the controlled system. Besides, an adaptive triggering function consisting of state-dependent and time-dependent threshold is developed to adjust the parameter of triggering threshold online. Then, a modified nonlinear and continuous observer-based controller with adaptive ETC strategy is developed to overcome the chattering phenomenon from the discontinuous controller. It is proved that under two controllers, the SP not only can be achieved in a fully distributed way without continuous communication for both the controller updates and the triggering condition detecting but also exclusion of “Zeno behavior” can be realized. Finally, the effective algorithms can be verified by giving numerical simulations related to mobile robots. [ABSTRACT FROM AUTHOR]

This paper investigates the controller design problem of networked control systems subject to cyber attacks. A hybrid-triggering communication strategy is employed to save the limited communication resources. State measurements are transmitted over a communication network and may be corrupted by cyber attacks. The aim of this paper is to design a controller for a new closed-loop system model with consideration of randomly occurring cyber attacks and the hybrid-triggering scheme. A stability criterion is obtained for the system stabilization by employing Lyapunov stability theory and stochastic analysis techniques. Moreover, the desired controller gain is derived by resorting to some matrix inequalities. Finally, a numerical example is exploited to demonstrate the usefulness of the proposed scheme. [ABSTRACT FROM AUTHOR]

The microscopic mechanisms of the negative electrocaloric effect (ECE) of the single-phase (1-x)(0.94Bi1/2Na1/2TiO3-0.06BaTiO3)-xBa1/2Sr1/2TiO3 (BNT-BT-BST) perovskite solid solutions fabricated via the sol-gel technique are explored in this study. Dielectric and mechanical relaxation analyses are employed to investigate the ferroelectric and structural transitions of the samples. The electrocaloric properties of the samples were measured by thermodynamics Maxwell relations. The difference between the depolarization temperature (Td) and the maximum dielectric constant temperature (Tm) was found to decrease with increasing BST content. Doping with BST stabilized the ferroelectric phase along with unifying the EC temperature changes (ΔT) to only negative values. The origin of the uniform negative ECE of BNT-BT-BST is discussed. [ABSTRACT FROM AUTHOR]

A hydrogenated amorphous silicon (a‐Si:H) thin‐film transistor (TFT) gate driver with negative bias stress on precharging node for noise sharing with high‐reliability 10.7‐in. automotive display has been proposed. The proposed circuit is composed of precharging block, pull‐up and pull‐down block, and noise‐free block. The precharging block not only starts up the gate driver but also reduces noise with 33% duty cycle. Duplicate output signals are responsible for turning on next stage to decrease the loading of output of gate line. Moreover, negative bias voltage recovering of TFTs could be created by setting another lower voltage source to lower the threshold voltage degradation of TFTs. According to lifetime test results, the proposed gate driver of 708 stages passes the extreme temperature range test (90°C and −40°C) for simulation and −40°C for measurement and remains stable over 800 h at 90°C test. Finally, this design is successfully demonstrated in a 10.7‐in. HD (1280 × RGB × 720) TFT‐LCD panel. [ABSTRACT FROM AUTHOR]

This paper addresses the control problem of the switched system with bounded actuators and average dwell-time. We present the switching rules for the designed controllers based on two kinds of parametric algebraic Riccati equation. The exponential stability of the switched system under the average-dwell time is ensured by the designed controllers and the switching rules. The dynamic performance of the control system is enhanced greatly by the proposed method. The simulation results illustrate the effectiveness and the usefulness of the obtained theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, we present a direct multirate adaptive control algorithm that ensures global stabilization of a class of (potentially unstable and invertible) linear time-invariant discrete-time plants of known order and relative degree one. An essential feature of our scheme is that no projections are needed, no appeal is made to the persistence of excitation arguments for the stability proof and it has a better transient performance than existing schemes. The implementation of the controller requires some prior information about its Markov parameters, namely, upper and lower bounds on the systems impulse response. It is directly applicable to plants with interlacing real poles and zeros, i.e., with Cauchy index equal to the plant order, provided the adaptation gain is restricted to be smaller than some value determined by the measure of relative primeness of the pole and zero polynomial. This class contains some practically interesting systems, for instance, resistor–inductor or resistance–capacitance circuits. [ABSTRACT FROM AUTHOR]

The problem of reliable controller design for two-dimensional (2-D) systems subject to extended dissipativity is investigated in this paper. Considering the wide usage of Roesser state-space model, a discrete-time Roesser model is introduced to describe 2-D systems. To reinforce the reliability of the system under consideration, actuator-failure model which may severely degrade performance, or even destabilize the system is introduced. Finally, the sufficient condition for the existence of reliable controller is presented to guarantee the mean square asymptotic stability and 2-D extended dissipativity of the closed-loop system under admissible actuator failures. The gains of 2-D controller are derived by means of the convex optimization method. A simulation result is exploited to verify the effectiveness and merits of the theoretical findings. [ABSTRACT FROM AUTHOR]

Click chemistry focuses on the development of highly selective reactions using simple precursors for the exquisite synthesis of molecules. Undisputedly, the CuI‐catalyzed azide–alkyne cycloaddition (CuAAC) is one of the most valuable examples of click chemistry, but it suffers from some limitations as it requires additional reducing agents and ligands as well as cytotoxic copper. Here, we demonstrate a novel strategy for the azide–alkyne cycloaddition reaction that involves a photoredox electron‐transfer radical mechanism instead of the traditional metal‐catalyzed coordination process. This newly developed photocatalyzed azide–alkyne cycloaddition reaction can be performed under mild conditions at room temperature in the presence of air and visible light and shows good functional group tolerance, excellent atom economy, high yields of up to 99 %, and absolute regioselectivity, affording a variety of 1,4‐disubstituted 1,2,3‐triazole derivatives, including bioactive molecules and pharmaceuticals. The use of a recyclable photocatalyst, solar energy, and water as solvent makes this photocatalytic system sustainable and environmentally friendly. Moreover, the azide–alkyne cycloaddition reaction could be photocatalyzed in the presence of a metal‐free catalyst with excellent regioselectivity, which represents an important development for click chemistry and should find versatile applications in organic synthesis, chemical biology, and materials science. [ABSTRACT FROM AUTHOR]

Surgical scalpel broken is rarely reported in posterior lumbar discectomy or fusion surgeries, but when it happens and even the broken part is deeply located in the disk space, there is no guideline to remove it during the initial surgery. A 56-year-old female with L3-L4 and L4-L5 disk herniation and stenosis underwent 2-level transforaminal lumbar diskectomy and fusion. The knife blade was broken in the L4-L5 disk space during the annulus resection. Despite a 1.5-hour trial for removal with fluoroscopy, the broken part gradually migrated to the anterior border of the disk space. Eventually, arthroscopy was used for retrieval, the blade tip was clearly recognized in the arthroscopic view, which improved the accuracy of the subsequent operation. The blade fragment was removed successfully within 30 minutes. Arthroscopic retrieval of a broken scalpel deeply located in the intradiskal space is recommended as an alternative method when conventional effort is unable to remove it, especially when the broken blade migrates anteriorly, which may provoke catastrophic consequences. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have been implicated in the regulation of resistance to radiotherapy in cervical cancer, which is a type of gynecological disease with high mortality in women around the world. Hence, our purpose is to delineate the involvement of LINC00958 in regulating cell sensitivity to radiotherapy in cervical cancer. LINC00958 expression in cervical cancer was assayed, followed by verification of the relationship among LINC00958, microRNA‐5095 (miR‐5095) and ribonucleotide reductase subunit M2 (RRM2). Hela cells were transduced with up‐/downregulation of miR‐5095 or RRM2, or LINC00958 silencing, respectively, and then treated with or without a 6 Gy dose of X‐ray irradiation. Then the cell proliferation, apoptosis, survival fraction rate, as well as sensitivity to radiotherapy, were assessed. Finally, xenograft tumor in nude mice was established by transplanting Hela cells transfected with sh‐LINC00958 and irradiated with 6 Gy of X‐ray. High expression of LINC00958 was revealed in The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis, as well as in radiation‐resistant patients, which was associated with lower sensitivity to radiotherapy in cervical cancer. Moreover, cervical cancer patients with higher LINC00958 expression exhibited a shorter overall survival according to Kaplan–Meier analysis. In addition, LINC00958 could regulate the expression of RRM2 by competing for miR‐5095. A combination of radiotherapy with LINC00958 silencing, RRM2 downregulation or miR‐5095 overexpression was found to inhibit cervical cancer cell proliferation and tumor growth, while promoting cell apoptosis both in vitro and in vivo. Collectively, our results suggest that LINC00958 could regulate RRM2 by competing to miR‐5095, which regulates cell sensitivity to radiotherapy in cervical cancer. [ABSTRACT FROM AUTHOR]

This paper considers the consensus problem of multiagent systems with the input-based triggering condition. A model-based approach is first given to estimate the relative interagent states between intermittent communications instead of absolute states. A novel consensus protocol consisting of the relative interagent states is proposed for the consensus problem. Besides, compared with some results on the triggering condition consisting of state measurement error, a new triggering condition is constructed based on the control input. Then, the consensus protocol is executed by every agent in a fully distributed way, which has the advantage that the controller design is related to the number of agents instead of using global information. Moreover, the bounds of parameters of the controller and the triggering condition can be obtained by the proposed algorithm simultaneously, which depends on the total number of agents in multiagent networks. The proposed control scheme can ensure that states of all agents can achieve consensus. It is shown that “Zeno behavior” does not appear under the proposed algorithm. Finally, an illustrative example is given to verify the proposed method. [ABSTRACT FROM AUTHOR]

Maize (Zea mays) smut is a common biotrophic fungal disease caused by Ustilago maydis and leads to low maize yield. Maize resistance to U. maydis is a quantitative trait. However, the molecular mechanism underlying the resistance of maize to U. maydis is poorly understood. Here, we reported that a maize mutant caused by a single gene mutation exhibited defects in both fungal resistance and plant development. maize mutant highly susceptible to U. maydis (mmsu) with a dwarf phenotype forms tumors in the ear. A map-based cloning and allelism test demonstrated that 1 gene encoding a putative arogenate dehydratase/prephenate dehydratase (ADT/PDT) is responsible for the phenotypes of the mmsu and was designated as ZmADT2. Combined transcriptomic and metabolomic analyses revealed that mmsu had substantial differences in multiple metabolic pathways in response to U. maydis infection compared with the wild type. Disruption of ZmADT2 caused damage to the chloroplast ultrastructure and function, metabolic flux redirection, and reduced the amounts of salicylic acid (SA) and lignin, leading to susceptibility to U. maydis and dwarf phenotype. These results suggested that ZmADT2 is required for maintaining metabolic flux, as well as resistance to U. maydis and plant development in maize. Meanwhile, our findings provided insights into the maize response mechanism to U. maydis infection. A gene encoding a putative arogenate dehydratase/prephenate dehydratase is essential for resistance to Ustilago maydis and plant development by maintaining metabolic flux in maize. [ABSTRACT FROM AUTHOR]

We present an ab initio dynamics investigation within a density-functional perturbation theory framework of the properties of the conjugated polymer poly-para-phenylene vinylene (PPV) in both the isolated chain and crystalline states. The calculated results show that for an isolated chain, most of the vibrational modes correspond to experimentally observed modes in crystalline PPV. However, additional hitherto unidentified modes have been observed in experiment and our calculations on crystalline material have allowed us to assign these. We also present the results of calculations of the polarizability and permittivity tensors of the material, which are in reasonable agreement with the typical values for conjugated polymers. Dynamical Born effective charges [S. Baroni, S. de Gironcoli, A. Dal Corso, and P. Giannozzi, Rev. Mod. Phys. 73, 515 (2001)] are calculated and compared with atomic charges obtained from Mulliken population analysis [M. D. Segall, C. J. Pickard, R. Shah, and M. C. Payne, Mol. Phys. 89, 571 (1996)] and we conclude that effective charges are more appropriate for use in the study of the dynamics of the system. Notable differences are found in the infrared-absorption spectra obtained for the isolated chain and crystalline states, which can be attributed to the differences in the crystalline packing effects, which clearly play a key role in influencing the lattice dynamics of PPV. [ABSTRACT FROM AUTHOR]

Evolution of Barkhausen jumps during the magnetization reversal process in disordered magnetic material is investigated. Based on the magnetoelastic effect (ΔE effect), we investigated the dynamics of Barkhausen jumps through an internal friction measurement of amorphous Fe-B-Mo ribbons. The ΔE caused by the Barkhausen jump is found to have a power-law scaling relation with the driving rate of magnetic field. Using numerical simulation, dynamics of Barkhausen avalanches in a realistic spin-lattice model for a disordered ferromagnet is analyzed. The dynamic scaling and inhomogeneous behavior observed in both experiments and theoretical models are presented and discussed. [ABSTRACT FROM AUTHOR]

The asymptotic mean square stability and ${{\mathcal {H}}}_{{2}}$ performance of the 2-D hidden Bernoulli jump system is analyzed in this paper. This system, essentially, has a bi-jumping property, in other words, its jumps depend on two jumping parameters, one is the Bernoulli process, the other is dependent on the Bernoulli process via a conditional probability matrix, they together determine which subsystem is active and are coined as hidden Bernoulli model. By means of Lyapunov function method, a sufficient condition is derived, which reveals that the system is asymptotically mean square stable and has a certain ${\mathcal {H}}_{{2}}$ performance if a set of matrix inequalities are satisfied. Furthermore, the issues of asynchronous control and filtering are addressed for 2-D Bernoulli jump system based on the hidden Bernoulli model and the derived result. Finally, numerical simulations indicate that these proposed theories and methods are reliable and efficient. [ABSTRACT FROM AUTHOR]

Bond breaking related with plastic deformation in a deformed metallic glass Zr 50 Cu 50 is investigated by molecular dynamics simulations. The results show that the spatial distributions of broken bonds are closely correlated with local shear strains, and the clustering behaviors of atoms with broken bonds (flow defects) are characterized with different stages of plastic deformation. The average distance among those clusters of flow defects decreases as the strains increase, which follows the curvature quadrupole model for flow defects in ideal amorphous solids. For the first time, the features of bond breaking processes are quantitatively measured with the chemical composition, bond length and orientation, bond pairs, local five-fold symmetry and quasi-nearest atoms, whose threshold values are important factors that could characterize the flow defects in metallic glasses under plastic deformation. The shape, orientation and energetics of flow defects quantitatively characterized by the bond breaking analysis thus facilitate our understanding on the deformation mechanisms in metallic glasses. Image 1 • Geometry, orientation and energetics of flow defects are revealed. • Chemical and structural factors are quantitatively measured. • A mechanistic model for flow defects is proposed. [ABSTRACT FROM AUTHOR]

The problem of fault detection for two-dimensional (2D) Markov jump systems characterized in the form of Roesser model is considered in this paper. An asynchronous fault detection filter is designed to produce a residual signal. The fault detection filter changes from one mode to another asynchronously with the plant's transitions. More specifically, the filter's mode transitions depend on the plant's mode through some conditional probabilities. Moreover, the transition probabilities of the plant and the conditional probabilities are only partially accessible, which appears more practical in real application systems. Under such a framework, sufficient conditions are developed to ensure the asymptotic mean square stability and (Q , R , S)- μ -dissipativity of the overall fault detection system. The parameters in the fault detection filter are given in terms of solutions of an optimization problem. Finally, some simulations are carried out to demonstrate the validity of the presented design techniques. [ABSTRACT FROM AUTHOR]

Abstract Si is one of the most attractive anode materials because of its extremely high theoretical capacity. In this study, we find that the (111) plane of crystalline Si in the anode is still present after 100 cycles and infer that it is the intercalation site of Li+ ions. We believe that Li+ ions are inserted into the tetrahedral sites of crystalline Si, and the (111) plane of Si collapses; meanwhile, expansion parallel to 〈220〉 crystal orientation occurs. After full lithiation, the crystalline Si is converted to amorphous silicon. In a Si/ composite anode, although the addition of amorphous carbon may improve the cycling performance of Si anode, the activation process is prolonged as the amount of amorphous carbon increased. We determine that amorphous carbon may reduce the diffusion of Li+, which increases the overpotential and results in the lower formation of the saturated Li/Si alloy. [ABSTRACT FROM AUTHOR]

Abstract In this article, we study the plasmonic resonance of infinite photonic crystal mounted by the double negative nanoparticles in two dimensions. The corresponding physical model is described by the Helmholz equation with so called Bloch wave condition in a periodic domain. By using the quasi-periodic layer potential techniques and the spectral theorem of quasi-periodic Neumann–Poincaré operator, the quasi-static expansion of the near field in the presence of nanoparticles is derived. Furthermore, when the magnetic permeability of nanoparticles satisfies the Drude model, we give the conditions under which the plasmonic resonance occurs, and the rate of blow up of near field energy with respect to nanoparticle's bulk electron relaxation rate and filling factor are also obtained. It indicates that one can appropriately control the bulk electron relaxation rate or filling factor of nanoparticle in photonic crystal structure such that the near field energy attains its maximum, and enhancing the efficiency of energy utilization. [ABSTRACT FROM AUTHOR]

Abstract The electrocaloric effects (ECE) in the composites consisting of ferroelectric (FE) copolymer poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) and (Bi 0.5 Na 0.5)TiO 3 - x BaTiO 3 nanoparticles (BNT-xBT, x = 0, 0.06, 1.0) are investigated. The anti-ferroelectric (AFE) nanofillers are found to affect more significantly than the FE nanofillers on the order-to-disorder phase transition near 60 °C in the copolymer matrix, as revealed by differential scanning calorimetry. Nevertheless, the influences of AFE nanofillers on the negative ECE are much weaker than that of FE nanofillers, suggesting that the negative ECE observed might not be associated with the AFE states in the composites. Instead, based on the dynamic mechanical analyses on the effects of nanofillers on the order-to-disorder phase transition in the copolymer matrix, the structural glassy states induced by the interaction between the nanofillers and the copolymer matrix are proposed to account for the negative ECE in the composite. This work provides an effective approach in enhancing the negative ECE, which is of technological importance to the implementation of electrocaloric refrigeration. Highlights • The anti-ferroelectric nanofillers are found to affect more significantly than the ferroelectric nanofillers on the order-to-disorder phase transition in P(VDF-TrFE) copolymer. • The structural glassy states induced by the interaction between the nanofillers and the copolymer matrix are proposed to account for the negative electrocaloric effect in the composite. • This work provides an effective approach in enhancing the negative electrocaloric effect, which is of technological importance to the implementation of electrocaloric refrigeration. [ABSTRACT FROM AUTHOR]