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Platooning is an effective way to reduce air resistance and fuel consumption in vehicular transportation. However, stochastically generated disturbances can significantly impact the string stability of platoons. This article proposes a novel control law, based on sliding mode control and leader‐predecessor communications, designed to improve the exponential mean‐square string stability of platoons with Ito‐type stochastic disturbances that consider friction force. Specifically, our approach employs a third‐order nonlinear dynamic model to capture the relevant spatiotemporal correlations present in vehicle platoons. The proposed longitudinal control strategy effectively stabilizes the platoons with time delay and was verified through simulation experimentation. In this study, the stability of sliding mode motion is thoroughly investigated by means of sub‐reachable and practical stability analysis with sliding mode control. The findings of this study provide a theoretical foundation for further research on vehicle platoons with increasingly complicated interference and time delays. Overall, our results demonstrate that our approach can achieve significant improvements in both fuel economy and exhaust emissions while maintaining high levels of string stability, further contributing to the development of efficient and sustainable transportation systems. [ABSTRACT FROM AUTHOR]

This paper investigates the interval-valued-multi-objective-optimization problem, whose objective function is a vector-valued max-plus interval function and the constraint function is a real-affine function. The strong and weak solvabilities of the interval-valued-optimization problem are introduced, and the solvability criteria are established. A necessary and sufficient condition for the strong solvability of the multi-objective-optimization problem is provided. In particular, for the bi-objective-optimization problem, a necessary and sufficient condition of the weak solvability is provided, and all the solvable sub-problems are found out. The interval optimal solution is obtained by constructing the set of all optimal solutions of the solvable sub-problems. The optimal load distribution is used to demonstrate how the presented results work in real-life examples. [ABSTRACT FROM AUTHOR]

To evaluate the stochastic responses of a newly designed virtual track train (VTT), a spatial dynamics model of VTT is developed theoretically in the paper. The structural characteristics of VTT; tyre-road dynamic interactions and road geometric random irregularity are considered. Additionally, a human-seat subsystem is built and integrated into the VTT system. This comprehensive dynamics model of the VTT enables detailed investigations on the system dynamic performance under complicated excitations. The Monte Carlo method is further adopted to assess the stochastic vibration characteristics of the VTT excited by random road irregularity. The results indicate that the vibration characteristics of the VTT are dominated by road irregularity. The lateral vibration of different carbodies of the VTT has little difference, while the vertical vibration of carbody 2 is worse than carbodies 1 and 3. Besides, the running speeds have significant influences on the running stability and ride comfort of the VTT. The increasing running speed and road irregularity level significantly increase the probability of running stability and ride comfort exceeding the threshold, which affects the operation of VTT. Furthermore, the proposed model is capable of being used for dynamics-related assessment and parameter optimisation design. [ABSTRACT FROM AUTHOR]

Amorphous Ag2S0.4Te0.6 shows outstanding ductility and promising thermoelectric properties at room temperature [He et al., Sci. Adv. 6, eaaz8423 (2020)], while the origin of its exceptional ductility is still not very clear. Here, we systematically investigate the temperature-dependent structure and thermodynamic behavior of the Ag2SxTe1−x (x = 0–1.0) system by means of in situ x-ray powder diffraction and dynamic thermodynamic analysis, respectively. Our experimental results reveal that the degree of crystallization in Ag2SxTe1−x varies continuously with the ratio of S and Te. The Ag2S0.4Te0.6 sample is composed of two amorphous phases, i.e., the S-rich and Te-rich Ag2(S,Te) glasses. The S-rich Ag2(S,Te) amorphous phase with the atomic ratio about Ag:S:Te = 66:21:13 is identified as the ductile phase, which is the origin of ductility in the Ag2S0.4Te0.6 sample. The Ag2S-based glass in the supercooled liquid state at room temperature behaves like a Newtonian fluid at low strain rates, leading to the excellent ductility of Ag2S0.4Te0.6. Our work demonstrates the great potential to design and realize flexible inorganic functional materials through amorphization. [ABSTRACT FROM AUTHOR]

The objective of this study was to review evidence on the effectiveness of vaccination in the prevention of human papilloma virus (HPV) infection at the cervix, anal, and oral. Systematic review and meta-analysis. The key search limitations are as follows: "Human Papilloma Virus", "Papilloma Virus, Human" "Human Papillomavirus Virus", "HPV" and "oral", "anus", "anal", "penis", "cervical," and "vaccine". Randomized controlled studies were searched and analyzed the risk ratio by Review Manager 5.3; funnel plot was adopted for publication bias analysis. Five randomized controlled studies enrolling 13,686 participants were retrieved, analyzed, and showed that HPV vaccination can effectively block HPV infection at cervical, anal, and oral. Subgroup analysis, moreover, proved that HPV 16/18 is more effective than HPV 6/11/16/18 in preventing anal and oral infections. HPV vaccine is efficacious in preventing HPV infection not only at cervical but also at anal and oral, as evidence supported by relevant studies. [ABSTRACT FROM AUTHOR]

A clear talking face video can be generated from a facial image driven by speech audio. However, the corresponding relationship between the generated video frames and the input speech audio is not well synchronized in the state-of-the-art methods. To solve this problem, this paper proposes a generative adversarial networks based talking face generation method driven by time–frequency features extracted from the input speech audio (TF 2). We design an audio time series encoder that extracts joint time–frequency features of the input speech audio. A multi-level wavelet transform is designed to transform the speech audio signal from time to different frequency domains, and then gate recurrent unit is adopted to extract tempo-semantic correlation features from multi-frequency domain of the audio signal, enhancing the realistic order of the generated video frames. A smoothened formulation of dynamic time warping was introduced into our time series discriminator to determine the similarity between the order of the generated and the sample video frames. Experiments on LRW, VoxCeleb2, and GRID datasets show an improvement in PSNR, SSIM, and Sync c o n f by 0.4 ∼ 3.75 dB, 0.01 ∼ 0.04, and 0.4 ∼ 2.7, respectively, and a reduction in LMD by 0.15 ∼ 3.99 compared to existing methods. The experimental results confirm that the method can generate acoustically synchronized talking faces. • A talking face generation method based on time–frequency domain features of speech is proposed. This method is capable of generating a wide range of talking faces by coupling audio and face image features. • An audio time series encoder is designed which extracts tempo-semantic correlation features from the multiple frequency domains of the speech. • A time series discriminator is designed with the introduction of a soft-DTW loss function. This discriminator is capable of correcting inaccurate time series features and providing accurate guidance to the generator. [ABSTRACT FROM AUTHOR]

The article focuses on the right-wing conservative force in the Republican Party is exerting increasingly prominent influence on the United States' domestic and foreign affairs. It mentions that the regarding the U.S policy toward China, previous Republican administrations were rational and pragmatic in general, with engagement and cooperation as the main policy orientation.

With the increasing demand of faster, safer, and more comfortable rail travel, the evacuated tube maglev train (ETMT) has gradually attracted hot concerns in recent years. According to Kantrowitz limit theory, ETMT may encounter chocked flows, leading to more complex generation and development of a series of waves as ETMT moves rapidly in the tube. To study the wave phenomena produced by ETMT running at the super high-speed, the computational domain geometry model was simplified and then 2-D axisymmetric compressible N-S equation was established in the paper. Dynamic mesh method and dynamic adaptive mesh method were used to simulate the real motion of ETMT and improve the capture accuracy of the waves respectively. Results show that the wave structure is mainly composed of expansion waves, reflected shock waves and normal shock waves as ETMT moves for enough time at the speed of 1250 km/h. The intensity of the normal shock wave in front of the head car experiences four states consisting of rapid increase, initial stability, sudden drop and final stability. In the wake, the flow velocity attenuates in a fluctuating way along the opposite motion direction of ETMT due to the complicated interaction between shock waves and expansion waves. • The 2-D axisymmetric model is established to simulate ETMT motion. • The combination methods of the layering mesh and adaptive mesh are used. • The different wave phenomena in the evacuated tube are revealed. • The propagation properties of various waves are observed. [ABSTRACT FROM AUTHOR]

Cr-doped ZnS (molar Cr:(Cr + Zn) between 0.51% and 19.69%) nanocrystallites have been prepared through co-precipitation method. The x-ray diffraction, transmission electron microscopy, and selected area electron diffraction results show that all the samples are in sphalerite structure with average particle size about 3 nm. No impurity phase relating to Cr element is found in all the samples. X-ray photoelectron spectroscopy spectra reveal that Cr was incorporated into ZnS lattice as Cr3+. It can be seen in the UV-visible absorption spectra that, besides the intrinsic band-gap absorption of ZnS below 370 nm, there are another two absorption bands (at 425 nm and 595 nm, respectively) in the visible light range, which are the characteristic bands of Cr3+. Photoluminescence spectroscopy was also used to characterize corresponding luminescence properties of the nanocrystallites. The band-edge emission in photoluminescence spectroscopy exhibits blue-shift as the concentration of Cr increases, and several emission peaks concerned with surface states and zinc vacancies were found in the wavelength range of 400 nm ∼ 500 nm. It is confirmed that Cr doping will bring about a considerable amount of zinc vacancies. Magnetic measurements indicated that all the samples are paramagnetic and the calculated effective magnetic moments μeff of Cr3+ were close to the theoretical value of 3.87 μB. Accordingly, it seems that zinc vacancies give no contribution to the overall magnetic response of the samples. [ABSTRACT FROM AUTHOR]

• Deep learning-based semantic segmentation on edge devices for field robot navigation. • 5 convolutional neural networks were studied for field robot navigation. • 5 scenes were studied to verify the applicability of proposed method. Smart agricultural machinery is emerging as the future trend for field robots, and the fully automatic robot has a great application prospect. However, it is a big challenge for robots to navigate in complex farmland environments. In this research, 5 deep learning-based computer vision methods under different field scenes for field navigation line extraction were studied and successfully deployed on an embedded system, which can be integrated into robots for automatic navigation in the future. The field road was segmented by the semantic segmentation algorithm at first, and then the navigation line is extracted from the segmented image by a polygon fitting method. Finally, all the models are transformed through the TensorRT library and deployed on the edge computing device Jetson Nano. In the experiment, five reprehensive semantic segmentation networks namely UNet, Deeplabv3+, BiseNetv1, BiseNetv2, and ENet networks were selected. Among the five networks, Deeplabv3+ is the most accurate. In five scenes, its average segmentation accuracy is 84.87 %, and the navigation line error is 9.59 pixels. Especially in the third scene with shadow and occlusion, it performs best, with only 8.34 pixel error, But the speed of Deeplabv3+ is only 9.7 FPS. ENet, BiseNetv1, and BiseNetv2 are lightweight networks. The speed of ENet is 16.8 FPS, BiseNetv2 is 17 FPS, and BiseNetv1 is 15.8 FPS. In segmentation accuracy and navigation line error, ENet performs better than BiseNet series networks, which are 84.94 % and 10.73 pixels, respectively. In the third scene with shadow and occlusion, it also performs slightly better than BiseNet series networks. In summary, deep learning-based semantic segmentation methods have strong robustness and stability in complex environment compared with previous research. Among all currently available neural networks, ENet has the best performance and good application potential in field navigation. [ABSTRACT FROM AUTHOR]

Ductile Ag 2 S 0.4 Te 0.6 shows promising thermoelectric properties and interesting phase transitions and structural features above room temperature. In this work, our experiments reveal that Ag 2 S 0.4 Te 0.6 is composed of a Ag 2 Te-based glass and a Ag 2 S-based supercooled liquid at room temperature. The Ag 2 Te-based glass preserves its amorphous state in the measured temperature range (20–303 K), while the Ag 2 S-based supercooled liquid crystallizes into a triclinic phase below 183 K, leading to respectively the glass and crystalline-like thermal transport of Ag 2 S 0.4 Te 0.6 near room temperature and at low temperature. At the crystallization point of the Ag 2 S-based phase, the electrical conductivity of Ag 2 S 0.4 Te 0.6 shows an anomalous change. The extremely wide supercooling region (183–420 K) of the Ag 2 S-based phase leads to the unprecedented ductility of Ag 2 S 0.4 Te 0.6. The thermoelectric figure of merit zT of Ag 2 S 0.4 Te 0.6 increases monotonically with increasing temperature and reaches ∼0.17 at 300 K, showing the great potential as a ductile thermoelectric inorganic. The Ag 2 S 0.4 Te 0.6 sample is composed of one Ag 2 Te-based glass and one Ag 2 S-based supercooled liquid at room temperature. The Ag 2 Te-based glass maintains its amorphous state at low temperatures (20 -303 K), while the Ag 2 S-based supercooled liquid crystallizes into a triclinic phase below 183 K, leading to unprecedented ductility, anomalous change in the electrical conductivity, as well as the glass/crystal mixture thermal transport of Ag 2 S 0.4 Te 0.6. [Display omitted] [ABSTRACT FROM AUTHOR]

Benzotriazole ultraviolet stabilizers (BUVSs) are widespread emerging pollutants, which can pose exposure risks to benthic organisms. However, the toxicity and mechanisms of BUVSs congeners in benthic clams are far from elucidated. In this study, Asian clams (Corbicula fluminea) were exposed to one of UV-234, UV-326, UV-329, or UV-P at environmentally relevant levels (0.1, 1, and 10 μg/L) for 21 days. Filtration rate (FR) was increased in clams exposed to all BUVSs and there were notable histopathologic changes, including irregular digestive lumen, lipid droplet vacuolation, and degraded epithelial cells. To determine the molecular underpinnings following BUVSs exposure, the transcriptome responses in digestive glands were compared. Differentially expressed genes shared among BUVSs treatments were associated with focal adhesion, TNF-α/NF-κB proinflammatory pathways, and apoptosis. Following this, biochemical analysis of biomarkers related to apoptosis were conducted to further validate response. Exposure to BUVSs inhibited anti-oxidant enzyme activity and induced oxidative stress. Heat shock proteins were also triggered with exposure, and there was an induction of caspase-3 and caspase-9 activity. Molecular responses were not identical in the digestive gland of C. fluminea when comparing responses to BUVSs; nevertheless conserved mechanism (impairment of the oxidative defense system, immune system disruption, and induction of apoptosis) among BUVSs congeners was noted. This study provides novel insight into the toxicity and hazards of BUVSs in benthic organisms. [Display omitted] • BUVSs increased filtering rate and caused pathological damage in C. fluminea. • BUVSs disrupted pathways related to focal adhesion, immunity, and apoptosis. • Toxicity of BUVSs was caused by oxidative stress and deteriorated cellular oxidative homeostasis. • Caspase 9, ROS, and FR are potential biomarkers for BUVSs exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] • UV-234 and UV-326 showed different bioaccumulation capacity and biotransformation. • Both BUVSs activated antioxidant defense system but inhibited lipid metabolism. • Metabolomic changes induced by BUVSs converged to cGMP-PKG pathway. • BUVSs have comparable toxicity in inducing apoptosis and neuroinflammation. Benzotriazole ultraviolet stabilizers (BUVSs) are emerging pollutants that are widely detected in aquatic ecosystems. While structure-dependent effects of BUVSs are reported, the relationship between biotransformation and toxicity outcomes remains unclear. In this study, zebrafish embryos were exposed to two common BUVSs (UV-234 and UV-326) at 1, 10, and 100 µg/L for up to 7 days. Comparison of their uptake and biotransformation revealed that the bioaccumulation capacity of UV-234 was higher than that of UV-326, while UV-326 was more extensively biotransformed with additional conjugation reactions. However, UV-326 showed low metabolism due to inhibited phase II enzymes, which may result in the comparable internal concentrations of both BUVSs in larval zebrafish. Both BUVSs induced oxidative stress while decreased MDA, suggesting the disturbance of lipid metabolism. The subsequent metabolomic profiling revealed that UV-234 and UV-326 exerted different effects on arachidonic acid, lipid, and energy metabolism. However, both BUVSs negatively impacted the cyclic guanosine monophosphate / protein kinase G pathway. This converged metabolic change resulted in comparable toxicity of UV-234 and UV-326, which was confirmed by the induction of downstream apoptosis, neuroinflammation, and abnormal locomotion behavior. These data have important implications for understanding the metabolism, disposition, and toxicology of BUVSs in aquatic organisms. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of the dynamical behaviours of a class of complex-valued neural networks with mixed time delays and impulsive effect. By separating the complex-valued neural networks into the real and the imaginary parts, the corresponding equivalent real-valued systems are obtained. Some sufficient conditions are derived for assuring the exponential stability of the equilibrium point of the system based on the vector Lyapunov function method and mathematical induction method. The obtained results generalise the existing ones. Finally, two numerical examples with simulations are given to demonstrate the feasibility of the proposed results. [ABSTRACT FROM AUTHOR]

Crystal structures, thermoelectric and mechanical properties of p-type PbSe-SrSe system were investigated over the full composition range. A continuous solid solution was formed in the PbSe-SrSe system. Na doping was used to modulate the carrier concentration of the system. The concentrations of Sr and Na for optimum thermoelectric performance of the system were determined to be 6% and 0.8%, respectively. The figure of merit ZT at 813 K was increased from 0.58 for non-Sr containing PbSe (with 2% Na doping) to 0.8 for Na and Sr optimized PbSe-SrSe solid solution. Then, Mn was introduced into the solid solution to further optimize the thermoelectric properties. The addition of Mn could generate nanosized particle-like Mn-rich precipitates in the matrix of PbSe-SrSe alloys and substantially reduce the lattice thermal conductivities. As a result, when half of the 6% Sr was replace by Mn, the ZT at 813 K could be further raised to ∼1.03. Furthermore, the presence of the Mn-rich precipitates could effectively strengthen the mechanical properties of the PbSe-SrSe alloys, which is favorable for the future practical applications of the PbSe materials. [ABSTRACT FROM AUTHOR]

A broadband noise source model based on Lighthill’s acoustic theory was used to perform numerical simulations of the aerodynamic noise sources for a high-speed train. The near-field unsteady flow around a high-speed train was analysed based on a delayed detached-eddy simulation (DDES) using the finite volume method with high-order difference schemes. The far-field aerodynamic noise from a high-speed train was predicted using a computational fluid dynamics (CFD)/Ffowcs Williams-Hawkings (FW-H) acoustic analogy. An analysis of noise reduction methods based on the main noise sources was performed. An aerodynamic noise model for a full-scale high-speed train, including three coaches with six bogies, two inter-coach spacings, two windscreen wipers, and two pantographs, was established. Several low-noise design improvements for the high-speed train were identified, based primarily on the main noise sources; these improvements included the choice of the knuckle-downstream or knuckle-upstream pantograph orientation as well as different pantograph fairing structures, pantograph fairing installation positions, pantograph lifting configurations, inter-coach spacings, and bogie skirt boards. Based on the analysis, we designed a low-noise structure for a full-scale high-speed train with an average sound pressure level (SPL) 3.2 dB(A) lower than that of the original train. Thus, the noise reduction design goal was achieved. In addition, the accuracy of the aerodynamic noise calculation method was demonstrated via experimental wind tunnel tests. [ABSTRACT FROM AUTHOR]

Synthetic phenolic antioxidant 2,4-di- tert -butylphenol (2,4-DTBP) has gained growing concerns due to relatively high concentrations in aquatic ecosystems. There are, however, significant knowledge gaps regarding its potential toxicity to aquatic organisms. In this study, zebrafish (Danio rerio) larvae were exposed to 0.01, 0.1, or 1 μM 2,4-DTBP for 6 d. Transcriptomic analysis of larvae revealed that biological processes related to anti-inflammatory function of macrophage M2 lineage were inhibited by 0.01 μM 2,4-DTBP. Decreases of transcripts related to the IL1B-MYD88-NF-κB pathway (i.e., il1b, il1rl1, myd88, irak4, irak1, traf6, ikbkg, nfkbia, nfkb) and protein levels of NF-κB in larvae intestine confirmed anti-inflammatory effects of 2,4-DTBP. Subsequently, larvae exposed to 2,4-DTBP were challenged with E. coli and showed higher survival rate, suggesting sustained activation of inflammation via LPS can be attenuated by 2,4-DTBP. Moreover, histological examination revealed that intestine barrier was compromised and there was an imbalance of intestine macrophage homeostasis. Food intake was also reduced following exposure to 0.1 and 1 μM 2,4-DTBP. In addition, a risk assessment revealed that 2,4-DTBP in surface water pose low to high ecological risks to aquatic organisms. Taken together, exposure to environmentally relevant concentrations of 2,4-DTBP could negatively affect immune response in zebrafish and may elicit ecological risk in fish population. [Display omitted] • 2,4-DTBP affects immunomodulation and the intestine barrier in zebrafish. • 2,4-DTBP exhibits anti-inflammatory properties via NF-κB pathway inhibition. • Exposure to 2,4-DTBP reduced feeding capacity in larvae. • 2,4-DTBP exerts moderate or high risk to fish. [ABSTRACT FROM AUTHOR]

A facial animation generation model can generate talking face videos from speech audio clips and face images. The frame sequence in the generated animation should be well synchronized with the source audio clips. A Facial Animation generation model based on an Adversarial Network (FAAN) model is proposed in this paper to generate video-speech synchronized facial animation from real human speech and a face image. The model maps features of the face image and the natural speech to a public space during the encoding process and then generates a frame sequence of a talking face according to the temporal coherence features contained in the speech fragments. To improve the synchronization accuracy between the generated video frame and source audio sequences, the model design should be a conditional least squares GAN, in which the temporal sequence of features extracted from the speech audio clips is inputted as a condition of the sequence discriminator. Furthermore, the temporal sequence of features extracted from the speech audio clips is added to the public space after the audio features are coupled with the facial features. Another conditional GAN, in which the input video frame is used as the condition of the frame discriminator, is designed in this model to improve the authenticity of the generated video frames. The model is ablated using Peak Signal-to-Noise Ratio (PSNR), Structural Similarity Index Measure (SSIM), and Frechette Inception Distance (FID). The experimental results show that the PSNR and SSIM scores of the FAAN model are better than those of the latest model on the GRID dataset; on the LRW dataset, the FANN model has the highest PSNR score. Finally, the validity of the proposed model is demonstrated by generating an optical flow diagram of the video frames, which shows that the model can elaborately drive the animation of the mouth in the generated video frames. Source code and videos are available at https://github.com/zjy-2020/Speech2video-FAAN/ • A novel GAN structure based on conditional least squares is proposed. • A new audio encoder is designed. • A sequence discriminator based on temporal coherent features and a video frame discriminator based on sample pictures are designed. [ABSTRACT FROM AUTHOR]

The solubility of naringin in the binary system of ethanol and water was measured by using UV spectrophotometric method at the maximum absorption wavelength (UV = 283 nm) from 283.15 K to 318.15 K under atmospheric pressure. The solubility increases with the increasing temperature and in the solvent system it exhibits a synergistic effect. The modified Apelblat model was applied to correlate the experimental solubility data, and the calculated solubilities were in good agreement with the experimental results. The process of the dissolution of naringin was always endothermic, and was influenced by two mechanisms which are enthalpy-driven and entropy-driven. Non-linear enthalpy–entropy compensation was found for naringin in the binary system of ethanol and water. [ABSTRACT FROM AUTHOR]

Designing and constructing heterojunction structures based on (0 0 1) facets dominated anatase TiO 2 has attracted much attention for acquiring higher photocatalytic activity. Here, SrTiO 3 /TiO 2 heterostructure nanosheets with different SrTiO 3 contents were fabricated by in situ hydrothermal reaction, in which anatase TiO 2 nanosheets with dominant exposed (0 0 1) facets were used as templates and initial reactants. Compared with pure TiO 2 nanosheets, SrTiO 3 /TiO 2 nanosheets exhibit better photocatalytic activity in degradation of rhodamine B (RhB) owing to the formation of nano–nano heterojunction. More importantly, the SrTiO 3 /TiO 2 composites exhibit excellent photocatalytic stability and outstanding catalytic activity with the increase of utilizing cycles. Particle size and morphology of SrTiO 3 nanostructures were found to dominate the photocatalytic activity of SrTiO 3 /TiO 2 composites through regulating the adhesion and aggregation of TiO 2 nanosheets as well as the number of reaction active sites. It is the first time to fabricate SrTiO 3 /TiO 2 heterojunction structure on limited two-dimensional nanosheets in situ , which is beneficial for understanding the growth of SrTiO 3 from TiO 2 in initial period. These results may further promote the applications of SrTiO 3 /TiO 2 composites in environment cleanup, solar cells, sensors and photonic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the problem of the dynamic behaviors of a class of complex-valued neural networks with mixed time delays. Some sufficient conditions for assuring the existence, uniqueness and exponential stability of the equilibrium point of the system are derived using the vector Lyapunov function method, homeomorphism mapping lemma and the matrix theory. The obtained results not only are convenient to check, but also generalize the previously published corresponding results. A numerical example is used to show the effectiveness of the obtained results. [Copyright &y& Elsevier]

Mesenchymal stem cells (MSCs) are multipotent progenitors that can undergo osteogenic differentiation under proper stimuli. We demonstrated that BMP9 is one of the most osteogenic BMPs. However, the molecular mechanism underlying BMP9-initiated osteogenic signaling in MSCs remains unclear. Through gene expression profiling analysis we identified several candidate mediators of BMP9 osteogenic signaling. Here, we focus on one such signaling mediator and investigate the functional role of cysteine-rich with EGF-like domains 2 (Creld2) in BMP9-initiated osteogenic signaling. Creld2 was originally identified as an ER stress-inducible factor localized in the ER-Golgi apparatus. Our genomewide expression profiling analysis indicates that Creld2 is among the top up-regulated genes in BMP9-stimulated MSCs. We confirm that Creld2 is up-regulated by BMP9 in MSCs. ChIP analysis indicates that Smad1/5/8 directly binds to the Creld2 promoter in a BMP9-dependent fashion. Exogenous expression of Creld2 in MSCs potentiates BMP9-induced early and late osteogenic markers, and matrix mineralization. Conversely, silencing Creld2 expression inhibits BMP9-induced osteogenic differentiation. In vivo stem cell implantation assay reveals that exogenous Creld2 promotes BMP9-induced ectopic bone formation and matrix mineralization, whereas silencing Creld2 expression diminishes BMP9-induced bone formation and matrix mineralization. We further show that Creld2 is localized in ER and the ER stress inducers potentiate BMP9-induced osteogenic differentiation. Our results strongly suggest that Creld2 may be directly regulated by BMP9 and ER stress response may play an important role in regulating osteogenic differentiation. [ABSTRACT FROM AUTHOR]

Background: Compelling evidence suggests that SIRT1, NAD+-dependent class III protein deacetylase, plays an important role in the prevention and treatment of atherosclerosis by counteracting inflammation. Cluster of differentiation 40 (CD40), as a pro-inflammatory cytokine, has been shown to participate in the pathophysiology of atherosclerosis. The relationship between SIRT1 and CD40, however, remained elusive. The present study was thus designed to explore the potential effect of SIRT1 on CD40 expression induced by tumor necrosis factor-α (TNF-α) and to disclose the underlying mechanism in CRL-1730 endothelial cells. Methods: mRNA and protein expressions were identified by quantitative real-time PCR and Western blot respectively. Subcellular localization of SIRT1 was detected by immunofluorescence analysis. SIRT1 small-interfering RNA (siRNA) was carried out for mechanism study. Results: TNF-α reduced SIRT1 expression and induced CD40 expression in CRL-1730 endothelial cells in a time- and concentration- dependent manner. Pretreatment with resveratrol (a potent SIRT1 activator) inhibited TNF-α-induced CD40 expression, while pretreatment with nicotinamide (class b HDACs inhibitor nicotinamide) or sirtinol (a known SIRT1 inhibitor), especially SIRT1 siRNA significantly augmented TNF-α-induced CD40 expression. The frther sudy idicated that PDTC (NF-κB inhibitor) pretreatment attenuated TNF-α-induced CD40 expression, and SIRT1 siRNA significantly augmented TNF-α-induced acetylated-NF-κB p65 (Lys310) expression. Conclusion: The present study provides the direct evidence that SIRT1 can inhibit TNF-α- induced CD40 expression in CRL-1730 endothelial cells by deacetylating the RelA/p65 subunit of NF-κB at lysine 310, which provides new insights into understanding of the anti-inflammatory and anti-athroscerotic actions of SIRT1. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Phosphatidylinositol 3-kinase α (PI3Kα) is a promising target for anticancer drug discovery due to its overactivation in tumor cells. To systematically investigate the interactions between PI3Kα and PIK75 which is the most selective PI3Kα inhibitor reported to date, molecular docking, molecular dynamics simulation, and ensuing energetic analysis were utilized. The binding free energy between PI3Kα and PIK75 is −10.04 kcal•mol using MMPBSA method, while −13.88 kcal•mol using MMGBSA method, which is beneficial for the binding. The van der Waals/hydrophobic and electrostatic interactions play critical roles for the binding. The binding mode of PIK75 for PI3Kα is predicted. The conserved hydrophobic adenine region of PI3Kα made up of Ile800, Ile848, Val850, Val851, Met922, Phe930, and Ile932 accommodates the flat 6-bromine imidazo[1,2-a]pyridine ring of PIK75. The 2-methyl-5-nitrophenyl group of PIK75 extends to the P-loop region, and has four hydrogen-bond arms with the backbone and side chain of Ser773 and Ser774. And the distinct conformation of the P-loop induced by PIK75 is speculated to be responsible for the selectivity profile of PIK75. The predicted binding mode of PIK75 for PI3Kα presented in this study may help design high affinity and selective compounds to target PI3Kα. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: In this paper, some sufficient conditions ensuring mean square exponential stability of the equilibrium point of a class of stochastic neural networks with reaction–diffusion terms and time-varying delays are obtained. The conditions involving the effect of diffusion terms reduce the conservatism of the previous results. Finally, we give a numerical example to verify the effectiveness of our results. [ABSTRACT FROM AUTHOR]

A high performance liquid chromatography (HPLC) coupled with an electrospray mass spectrometry (ESI-MS) method was developed for the determination of six bioactive compounds in a Buyang Huanwu decoction (BYHWD), which was composed of seven spices of Traditional Chinese Medicines (TCMs). The separations were performed on a Shim-pack (VP-ODS) C18 analytical column (5 μm, 250 × 4.6 mm ID, Shimadzu, Kyoto, Japan) with the column temperature maintained at 30°C. A linear gradient elution of A (0.1% formic acid solution) and B (100% acetonitrile) was used at a flow rate of 0.8 mL/min. The six compounds in BYHWD were identified by an Agilent-1100 HPLC system with a photodiode array detector coupled with an LC/MSD Trap SL electrospray ion mass spectrometer, and the contents of these compounds were determined by a Shimadzu 20A HPLC system coupled with a LCMS-2010EV quadrupole mass spectrometer. The standard calibration curves were linear with regression coefficient r2 > 0.99. The intra-day and inter-day precisions of this method were evaluated with the relative standard deviation values (less than 2.06% and 2.88%, respectively). The recoveries of the six investigated compounds exceeded 96%. This method was successfully used to determine the six target compounds in BYHWD. [ABSTRACT FROM AUTHOR]

• The VCSELs based on asymmetric confinement by oxide layer itself is an ideal solution to obtain polarization stability. • Theoretical simulations guide the selection of asymmetric oxidation apertures. • The oxidation time influences the asymmetry of oxide aperture. • The asymmetry of oxide aperture influences the state of the emitting mode. Given the high symmetry of vertical-cavity surface-emitting lasers (VCSELs) along their emission axis, these lasers demonstrate intrinsic polarization instability. In this study, we report the anisotropy oxide apertures of VCSEL formed by the unsymmetrical airflow distribution during the wet oxidation process. The polarization directions of VCSELs with anisotropy oxide apertures are well-controlled. VCSELs with oxide apertures of 2 μm × 4.6 μm achieve an orthogonal polarization suppression ratio of more than 20 dB and side-mode suppression ratio of more than 25 dB. In addition, an asymmetric far field distribution is observed, which can be ascribed to the asymmetric oxide apertures. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the impulsive Cohen–Grossberg neural network model with time-varying delays is considered. Applying the idea of vector Lyapunov function, M-matrix theory and inequality technique, several new sufficient conditions are obtained to ensure global exponential stability of equilibrium point for impulsive Cohen–Grossberg neural network with time-varying delays. These results generalize a few previous known results and remove some restrictions on the neural network. An example is given to show the effectiveness of the obtained results. It is believed that these results are significant and useful for the design and applications of the Cohen–Grossberg neural network. [Copyright &y& Elsevier]

Abstract: A novel crown-shaped heteropolytungstate is formed by covalently linking two [PW11O39]7− and two [PW9O34]9− fragments with four WO6 octahedra, which represents not only the largest tungstophosphate constructed from two types of building blocks without considering the 4f lanthanide or other 3d transition metal ion linkers but also the highest degree of aggregation known in the large clusters incorporating monovacant lacunary anions. [Copyright &y& Elsevier]

Abstract: A high performance liquid chromatography (HPLC) coupled with electrospray tandem mass spectrometry (ESI-MS) and ultraviolet detector (UV) has been developed for the simultaneous analysis of eight bioactive compounds in Danning tablet (including hyperin, hesperidin, resveratrol, nobiletin, curcumine, emodin, chrysophanol, and physcion), a widely used prescription of traditional Chinese medicine (TCM). The chromatographic separation was performed on a ZORBAX Extend C18 analytical column by gradient elution with acetonitrile and formate buffer (containing 0.05% formic acid, adjusted with triethylamine to pH 5.0) at a flow rate of 0.8ml/min. The eight compounds in Danning tablet were identified and their MS n fractions were elucidated by using HPLC-ESI-MS, and the contents of these compounds were determined by using HPLC-UV method. The standard calibration curves were linear between 5.0 and 100μg/ml for hyperin, 10–200μg/ml for hesperidin, 1.0–150μg/ml for resveratrol, 2.0–120μg/ml for nobiletin, 2.0–225μg/ml for curcumine, 20–300μg/ml for emodin, 2.0–200μg/ml for chrysophanol, and 20–250μg/ml for physcion with regression coefficient r 2 >0.9995. The intra-day and inter-day precisions of this method were evaluated with the R.S.D. values less than 0.7% and 1.3%, respectively. The recoveries of the eight investigated compounds were ranged from 99.3% to 100.2% with R.S.D. values less than 1.5%. This method was successfully used to determine the 8 target compounds in 10 batches of Danning tablet. [Copyright &y& Elsevier]

Abstract: In this work, the conditions ensuring existence, uniqueness, and global exponential stability of the equilibrium point of interval neural networks with variable delays are studied. Applying the idea of the vector Lyapunov function, and M-matrix theory, the sufficient conditions for global exponential stability of interval neural networks are obtained. [Copyright &y& Elsevier]

Abstract: In this Letter, the conditions ensuring existence, uniqueness of the equilibrium point of Cohen–Grossberg neural networks with variable delays are obtained under more general assumption about activation functions. Applying idea of vector Liapunov function, and M-matrix theory, the sufficient conditions for global exponential stability of Cohen–Grossberg neural networks are obtained. These results generalize a few previous known results and remove some restrictions on the neural networks. [Copyright &y& Elsevier]

In this paper, the existence and uniqueness of the equilibrium point and absolute stability of a class of neural networks with partially Lipschitz continuous activation functions are investigated. The neural networks contain both variable and unbounded delays. Using the matrix property, a necessary and sufficient condition for the existence and uniqueness of the equilibrium point of the neural networks is obtained. By constructing proper vector Liapunov functions and nonlinear integro-differential inequalities involving both variable delays and unbounded delay, using M-matrix theory, sufficient conditions for absolutely exponential stability are obtained. [Copyright &y& Elsevier]

In this paper, the existence and uniqueness of the equilibrium point and absolute stability of a class of cellular neural networks with globally Lipschitz continue activation functions are investigated. The neural networks contain both variable and unbounded delays. The necessary and sufficient condition for the existence and uniqueness of the equilibrium point of the neural networks is obtained. By constructing proper vector Liapunov functions, nonlinear integrodifferential inequalities involving both variable delays and unbounded delay, which are corresponding to the neural networks, are established. By using M-matrix theory and qualitative property of the integrodifferential inequalities, the sufficient conditions for absolute stability (global asymptotic stability) are obtained. [Copyright &y& Elsevier]

In this paper, one approach is employed to investigate the existence and uniqueness of the equilibrium and the global attractivity of Hopfield neural network models. Without assuming the boundedness, monotonicity, and differentiability of the activation functions, by using M-matrix theory, Liapunov functions are constructed and employed to establish sufficient conditions for global asymptotic stability. [Copyright &y& Elsevier]

In this paper, without assuming the boundedness, monotonicity, and differentiability of the activation functions, we present new conditions ensuring existence, uniqueness, and global asymptotical stability of the equilibrium point of cellular neural network models with fixed time delays. The results are applicable to both symmetric and nonsymmetric interconnection matrices, and all continuous nonmonotonic neuron activation functions. [Copyright &y& Elsevier]

This paper introduces a novel trajectory calculation method for achieving continuous low-thrust transfers from the geostationary orbit to libration point orbits within the Earth-Moon restricted three-body framework. Low-thrust engines can offer benefits such as high specific impulse and long operating lifetimes, making them suitable for deep space exploration. However, the primary challenge lies in the low thrust level, leading to prolonged flight duration for spacecraft to overcome Earth's gravitational pull. Furthermore, the transfer trajectories exhibit multiple revolutions around the Earth, adding complexity to the calculations. To solve these difficulties, a novel trajectory computation method is presented, which for the first time discusses dynamical evolution beyond a predefined time interval in the context of an optimal control problem specific to low-thrust engines. This method employs a backward integration technique applied to the known optimized solution, coupled with a deliberate extension of the flight time to generate an initial guess for subsequent trajectory optimization, significantly simplifying the computational procedure. Several application scenarios involving transfer from the geostationary orbit to libration point orbits are demonstrated. The results confirm the effectiveness of this method, providing a rapid computational strategy for similar low-thrust transfer missions. [ABSTRACT FROM AUTHOR]

Hopf bifurcations and nonlinear oscillations for a railway passenger car are studied in this article. The vehicle is considered as a multi-rigid-body system with 17 degrees of freedom. During the wheel/rail impact when the wheelset lateral displacement is greater than the wheel flange clearance, the vehicle/track coupling model is considered. The rail is modelled as an Euler-Bernoulli beam extended to infinity and discretely supported by sleepers. The lateral and torsional vibration of the rail is taken into account. Two propositions for searching the Hopf bifurcation point of the system are given. Then linear and nonlinear critical speeds of the vehicle system with different primary suspension stiffness, periodic solutions and chaos in the system are investigated. [ABSTRACT FROM AUTHOR]

• Supplementary red light accelerates the ripening of tomato fruit. • Supplementary red light promotes ethylene biosynthesis in tomato fruit. • Supplementary red light up-regulates the expressions of genes encoding phytochrome. • Supplementary red light facilitates the accumulation of phytoene in tomato fruit. In greenhouse tomato production, the lower canopy of tomato plants is often shaded by the neighbouring tomato plants. Supplementary lighting can be used to provide sufficient light energy for plants. Red light is regarded as the most efficient spectrum in supplementary lighting. Whether and how supplementary red light in the ambient of sunlight affect the ripening of tomato remain to be elucidated. In this research, the impacts of supplementary red light on tomato ripening were examined by comparing the impacts of supplementary red light on ripening-related regulators, ethylene synthesis, ethylene signaling, carotenoid synthesis and light signaling in Micro-Tom wild type tomato fruit and ripening-inhibitor (rin) mutant. Supplementary red light did not affect the fruit ripening of rin mutant, because the deficiency of SlRIN resulted in down-regulation of genes encoding ripening-related regulators and suppression of ethylene biosynthesis. The wild type tomato fruit under supplementary red light showed accelerated color transition during ripening, which was associated with the increased expressions of genes encoding ripening-related regulators and ethylene biosynthesis. The increased expressions of genes encoding phytochrome in wild type tomato fruit under supplementary red light might reduce the level of phytochrome-interacting factors, resulting in higher activation of the phytoene synthase and overaccumulation of phytoene. Supplementary red light in ambient sunlight resulted in the accumulation of phytoene and the earlier ripening in tomato fruit, which depended on ethylene production. [ABSTRACT FROM AUTHOR]

Aerothermal effects generated by the evacuated tube maglev train (ETMT) cannot be ignored as it moves at the super high-speed. The study on the aerothermal mechanism induced by ETMT is of great significance to the design and application of heatproof materials on the skins of tube wall and vehicle. Based on the combination methods of dynamic layering mesh and dynamic adaptive mesh, the high-speed movement process of ETMT was reproduced by numerical simulation. The results show that the main frequency and amplitude of the ETMT skin temperature fluctuation in the "steady" stage have certain stochastic characteristics in spatial distribution. Separation and reattachment of the boundary layer contribute to decrease and increase of the ETMT skin temperature respectively. Besides, both expansion wave and shock wave near tail car increase the ETMT skin temperature. The normal shock wave in front of ETMT makes the tube wall temperature reach the maximum, while the normal shock wave behind ETMT makes the tube wall temperature reach relatively low due to the complicated interactions between reflected shocks wave and expansion shocks wave in wake. In wake, the tube wall temperature caused by the shock wave is higher than that caused by the expansion wave at any time. • The combination methods of the motion mesh and adaptive mesh are used to simulate ETMT motion. • Frequency domain characteristics of ETMT skin temperature are studied. • Typical spatial distributions of ETMT skin temperature are observed. • Aerothermal effects of various waves on the tube skin are considered. [ABSTRACT FROM AUTHOR]

Since the discovery of superior ductility in semiconducting Ag2S at room temperature, Ag2S‐based inorganics attract ever‐increasing attention as ductile thermoelectrics (TEs) for flexible electronics, while the monoclinic to cubic structure transition near room temperature (≈455 K for Ag2S) of these materials leads to instability of their structures and properties. In this work, single‐phase cubic Ag2S1−2xSexTex (x = 0.13–0.33) samples are stabilized at room temperature via entropy engineering. In comparison with pure Ag2S, the random mixing of S, Se, and Te at the anion site results in increased configuration entropy, improved electrical conductivity, decreased lattice thermal conductivity, and thus significantly enhanced TE properties of cubic Ag2S1−2xSexTex samples. By further optimizing the carrier concentration through introducing Ag vacancies, the slightly Ag‐deficient Ag1.98S0.34Se0.33Te0.33 sample achieves a power factor of 6.1 µW cm−1 K−2 and a dimensionless figure of merit zT of 0.4 at room temperature. In the measured temperature range of 300–500 K, this cubic sample with excellent ductility shows not only a record average zT value of 0.62 in ductile inorganics but also very stable TE properties, demonstrating the great potential of entropy engineering in the design of high‐performance ductile TE inorganics. [ABSTRACT FROM AUTHOR]

By introducing the Lennard-Jones potential into the interaction of vehicles, a new cellular automata model of traffic flow is proposed, in which the fixed probability of randomisation of cellular automata is replaced by the state transition probability of cell sites. The proposed model considers that the driver is affected by the interactional potential of vehicles before him/her, and the decision-making process is related to the value of the interactional potential. The model is more suitable for the driver's random decision-making process which is based on the stochastic behaviour of traffic flow. The fundamental diagram (flow density relationship) of the proposed model is obtained, and the complex traffic phenomenon is reproduced through numerical simulation. [ABSTRACT FROM AUTHOR]

The design of the cavity structure is one of the effective means to reduce the resistance and noise of the pantograph installed on the roof of a high-speed train. This research first investigated the flow and acoustic characteristics of a pantograph with four different cavity structures, namely the rectangular cavity (original), the rounded edge cavity (case 1), and the other two rounded edge cavities with asymmetric (case 2) and symmetric (case 3) connecting tubes. The results show that the three cavity treatment methods all improve the aerodynamic performance, and the cavity model of case 2 is determined to be the optimal structure. In case 2, the tube installed at the front of the cavity destroys the separated shear layer and reduces the unstable airflow, reducing cavity resistance and noise by 9.64% and 5.2 dBA (A-weighted decibels), respectively. The pantograph is placed inside the previously determined improved cavity, which reduces the airflow velocity and the recirculation region upstream of the pantograph, decreases the impingement on the components in the middle and lower regions of the pantograph and the generation of highly intense vortices, and improves the wake structure and flow separation at the rear surface of the cavity. Thus, the aerodynamic drag for the pantograph and the whole system is reduced by 3.82% and 3.25%, respectively, and the aerodynamic noise is also decreased by 1.4 and 1.9 dBA, respectively. This study provides a novel structural design for the pantograph cavity region. [ABSTRACT FROM AUTHOR]

Searching for new materials with intrinsically low lattice thermal conductivity is crucial for the exploration of high‐performance thermoelectric materials. Herein, the layered compound GeBi2Se4 with intrinsically low lattice thermal conductivity is discovered, and its thermoelectric performance optimization is accelerated by machine learning. The ultralow lattice thermal conductivity of 0.53 W m−1 K−1 at room temperature for the GeBi2Se4 sample can be ascribed to the large anharmonicity and miscellaneous crystal defects. By alloying tellurium (Te) at the selenium (Se) site, the lattice thermal conductivity is further reduced due to the alloy scattering effect and chemical bond softening while the density‐of‐states effective mass of electrons is significantly increased. Finally, the best n‐type thermoelectric GeBi2Se1.9Te2.1 sample with a dimensionless figure of merit zT of 0.56 at 460 K is screened out by machine learning and verified by experiments, which increases by 140% in comparison with the pristine GeBi2Se4. [ABSTRACT FROM AUTHOR]

N‐type ZrNiSn‐based alloys reach a record thermoelectric figure of merit zT ≈1.2 by increasing the carrier concentration to 4–5 × 1020 cm−3. In this work, It is reported that a comparable zT can also be realized in trace Ru‐doped ZrNiSn‐based alloy at even lower temperature by decreasing the carrier concentration. Compared to the previously reported Co doping, the doping of Ru results in a more effective reduction in carrier concentration, and thus higher Seebeck coefficient, lower electronic thermal conductivity, and enhanced thermoelectric performance. The electronic specific heat coefficient of the ZrNi1‐xRuxSn sample remains constant with increasing Ru content, indicating no obvious change in the density of states effective mass. Theoretical calculations show that the doping of Ru has negligible effect on the bottom of conduction band. The lattice thermal conductivity is further reduced by alloying Ti and Hf at the Zr site, and the bipolar diffusion is suppressed by doping of 0.5 at.% Sb. As a result, Ti0.25Zr0.5Hf0.25Ni0.99Ru0.01Sn0.995Sb0.005 reaches not only a zT value of 1.1 at 773 K but also a record average zT value of 0.8 in 300 to 873 K, demonstrating the effectiveness of trace Ru doping on boosting the thermoelectric performance of ZrNiSn‐based alloys. [ABSTRACT FROM AUTHOR]

Searching for new materials with intrinsically low lattice thermal conductivity is crucial for the exploration of high‐performance thermoelectric materials. Herein, the layered compound GeBi2Se4 with intrinsically low lattice thermal conductivity is discovered, and its thermoelectric performance optimization is accelerated by machine learning. The ultralow lattice thermal conductivity of 0.53 W m−1 K−1 at room temperature for the GeBi2Se4 sample can be ascribed to the large anharmonicity and miscellaneous crystal defects. By alloying tellurium (Te) at the selenium (Se) site, the lattice thermal conductivity is further reduced due to the alloy scattering effect and chemical bond softening while the density‐of‐states effective mass of electrons is significantly increased. Finally, the best n‐type thermoelectric GeBi2Se1.9Te2.1 sample with a dimensionless figure of merit zT of 0.56 at 460 K is screened out by machine learning and verified by experiments, which increases by 140% in comparison with the pristine GeBi2Se4. [ABSTRACT FROM AUTHOR]

A class of switched neural networks (SNNs) in the presence of parameter uncertainties, impulsive effects, and both variable and continuously distributed delays are investigated. Firstly, the existence and uniqueness conditions of equilibrium point of each subsystem are proposed, which implies that the addressed SNNs has a unique equilibrium point. Secondly, we derive several sufficient conditions for robust exponential stability under average dwell time (ADT) switching and arbitrary switching, respectively. These conditions are formulated in terms of algebraic inequalities and M-matrices and are derived by employing inequality technique incorporated with the idea of vector Lyapunov function. Lastly, the less conservativeness and effectiveness of the obtained results over some existing literature are verified by simulation examples. [ABSTRACT FROM AUTHOR]