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IMPORTANCE: The effect of argatroban in patients with acute ischemic stroke (AIS) and early neurological deterioration (END) is unknown. OBJECTIVE: To assess the efficacy of argatroban for END in AIS. DESIGN, SETTING, AND PARTICIPANTS: This open-label, blinded–end point, randomized clinical trial was conducted from April 4, 2020, through July 31, 2022. The date of final follow-up was October 31, 2022. This was a multicenter trial. Eligible patients were adults with AIS who experienced END, which was defined as an increase of 2 or more points on the National Institutes of Health Stroke Scale within 48 hours from symptom onset. Patients who withdrew consent, experienced duplicate randomization, or were lost to follow-up were excluded from the study. INTERVENTIONS: Patients were randomly assigned to the argatroban group and control group within 48 hours of symptom onset. Both groups received standard therapy based on guidelines, including oral mono or dual antiplatelet therapy. The argatroban group received intravenous argatroban for 7 days (continuous infusion at a dose of 60 mg per day for 2 days, followed by 20 mg per day for 5 days) in addition to standard therapy. MAIN OUTCOME AND MEASURE: The primary end point was good functional outcome at 90 days, defined as a modified Rankin Scale score of 0 to 3. RESULTS: A total of 628 patients (mean [SD] age, 65 [11.9] years; 400 male [63.7%]) were included in this study (argatroban group, 314 [50%] and control group, 314 [50%]). Of these, 18 withdrew consent, 1 had duplicate randomization, and 8 were lost to follow-up. A total of 601 patients with stroke were included in the intention-to-treat analysis. Finally, 564 patients were included in the per-protocol analysis as 6 participants in the argatroban group and 31 participants in the control group did not follow the complete protocol. The number of patients with good functional outcome at 90 days was 240 (80.5%) in the argatroban group and 222 (73.3%) in the control group (risk difference, 7.2%; 95% CI, 0.6%-14.0%; risk ratio, 1.10; 95% CI, 1.01-1.20; P = .04). The proportion of symptomatic intracranial hemorrhage was 3 of 317 (0.9%) in the argatroban group and 2 of 272 (0.7%) in the control group (P = .78). CONCLUSIONS AND RELEVANCE: Among patients with AIS with END, treatment with argatroban and antiplatelet therapy resulted in a better functional outcome at 90 days. This trial provided evidence to support the use of argatroban in reducing disability for patients with END. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04275180

Crosswind disturbances may cause rollover or lane departure of truck and centre-axle-trailer (TCAT) combinations. To increase the safety of TCATs, a crosswind model is introduced and a 3 degrees of freedom (DOF) yaw-plane model is generated for developing a lateral stability control technique. Numerical simulation is conducted to examine the resulting dynamic responses under varying crosswind disturbances. To verify the 3-DOF model, the simulation results under a single lane-change (SLC) manoeuvre under a crosswind disturbance are compared against those based on the corresponding nonlinear TruckSim model. To effectively reject crosswind disturbances, a braking torque distribution strategy is proposed, by which the direct yaw moment control (DYC) is implemented using a fuzzy-PID algorithm. The simulation shows that the directional performance of TCAT is improved when the DYC activates under crosswind disturbances. The proposed active safety technique can reduce the risk of crosswind-induced instabilities of TCATs.

Since the outbreak of coronavirus disease 2019 (COVID-19), the epidemic has been spreading around the world for more than 2 years. Rapid, safe, and on-site detection methods of COVID-19 are in urgent demand for the control of the epidemic. Here, we established an integrated system, which incorporates a machine-learning-based Fourier transform infrared spectroscopy technique for rapid COVID-19 screening and air-plasma-based disinfection modules to prevent potential secondary infections. A partial least-squares discrimination analysis and a convolutional neural network model were built using the collected infrared spectral dataset containing 857 training serum samples. Furthermore, the sensitivity, specificity, and prediction accuracy could all reach over 94% from the results of the field test regarding 968 blind testing samples. Additionally, the disinfection modules achieved an inactivation efficiency of 99.9% for surface and airborne tested bacteria. The proposed system is conducive and promising for point-of-care and on-site COVID-19 screening in the mass population.

With stringent requirements on fuel economy and greenhouse gas emissions, we are facing a challenge to reduce road vehicle aerodynamic drags. While travelling in a platoon, the wake of preceding vehicle can affect the aerodynamic characteristics of following vehicle. Due to platoon airflow field, the drag of each vehicle changes, posing impact on vehicle's fuel consumption. In the study, the Motor Industry Research Association (MIRA) car models, namely notchback, fastback, and squareback, are generated. The airflow fields for isolated single-vehicle models are imitated by computational fluid dynamics (CFD) simulation. The drag coefficient errors between simulation and experiment are less than 6%, indicating good agreement between the simulation and wind tunnel test. Using CFD simulation, we explore the effects on aerodynamic properties of vehicles in platoon due to contributing factors of nonuniform inter-vehicle separation distance, number of vehicles, and vehicle shapes. Insightful findings from the study will provide guidelines for developing autonomous vehicle platoons.

With the rapid development of highway networks and logistics industry in China, medium-duty trucks have been increasingly used for highway and urban area freight transportation. The aerodynamic drag reduction of medium-duty trucks is of significant importance for improving highway transportation efficiency, enhancing fuel economy, and reducing greenhouse emissions. This paper proposes, compares and evaluates seven designs of tail air-deflector, which are devised to reduce aerodynamic drag of a medium-duty truck. The impacts of the shapes and/or configurations of tail air-deflector on the aerodynamic characteristics of the truck are studied using computational fluid dynamics (CFD) simulation. The results attained from the comparative study will provide guidelines for the design of airflow control devices for commercial vehicles to effectively reduce aerodynamic drag.

Increasing service time makes the axlebox bearing of railway vehicle vulnerable to develop a fault in inner or outer races, which can cause some serious adverse effects on a railway vehicle’s safe operation. To tackle this problem, we established a railway vehicle vertical-longitudinal dynamic model with inner/outer races faults of axlebox bearing and validated it by experimental data. We utilized the time-synchronous average (TSA) technology to filter the raw signals and studied their vibration features. The results show that the longitudinal vibration features are more sensitive for inner race fault identification, while the vertical vibration features are more suitable for outer race fault identification. For inner race fault identification, the indicator peak-to-peak value (PPV) that increases 1056% relative to the healthy state at the most severe fault performs the best sensitivity. For outer race fault identification, the indicator skewness value (SV) that increases 518% relative to the healthy state at the most severe fault exhibits the best performance. The research work can provide meaningful guidance for accurate diagnosis of axlebox bearing faults of railway vehicles.

Integrating lithium metal anodes with polymer electrolytes is a promising technology for the next generation high-energy-density rechargeable batteries. As the progress is often hindered by the dendrite growth upon cycling, quantifying three-dimensional (3D) microstructures of dendrites in polymer electrolytes is essential to better understanding of dendrite formation for the development of mitigation strategies. Techniques for 3D quantification and visualization of dendrites, especially those with low Li contents, are rather limited. This study reports quantitative measurements of the spatial distribution of Li dendrites grown in solid polymer electrolytes using 3D tomographic neutron depth profiling (NDP) with improved spatial resolution, compositional range, and data presentation. Data reveal heterogeneous distribution of Li over length scales from tens nanometers to centimeters. While most dendrites grow from the plating toward the stripping electrode with dwindling Li quantities, dendrites apparently grown from the Li-stripping electrode are also observed. The discovery is only possibly due to the unique combination of the high specificity and high sensitivity of the neutron activation analysis of Li isotope.

This article proposes a design of a tracking controller for autonomous articulated heavy vehicles (AAHVs) using a nonlinear model predictive control (NLMPC) technique. Despite economic and environmental benefits in freight transportation, articulated heavy vehicles (AHVs) exhibit poor directional performance due to their large sizes, multi-unit vehicle configurations, and high centers of gravity (CGs). AHVs represent a 7.5 times higher risk of traffic accidents than single-unit vehicles (e.g. rigid trucks, cars, etc.) in highway operations. Human driver errors cause about 94% of traffic collisions. However, little attention has been paid to autonomous driving control of AHVs. To increase the safety of AHVs, we design a novel NLMPC-based tracking controller for an AHV, that is, a tractor/semi-trailer combination, and this tracking controller is distinguished from others with the feature of controlling both the lateral and longitudinal motions for both the leading and trailing units. To design the tracking controller, a new prediction AHV model is developed, which represents both the lateral and longitudinal dynamics of the vehicle and captures its rearward amplification feature over high-speed evasive maneuvers. With the proposed tracking controller, the AAHV tracks the predefined reference path and follows a planned forward-speed scheme. Co-simulation demonstrates the effectiveness and robustness of the proposed NLMPC tracking controller.

A well-aligned composition-graded CuSi nanorod array structure has been fabricated by a simple oblique angle codeposition technique in a physical vapor deposition system. The Cu and Si graded composition distribution in the nanorods was confirmed by their elemental mapping and depth profiles. The crystal structure evolution with the nanorod length was revealed by both electron and X-ray diffractions. The size evolution of the CuSi nanorods followed a power law, which results from the combination effects of geometric shadowing and limited surface atomic diffusion. Such a graded composition distribution could relax the stress between the nanorods and the substrate, and is promising for applications where improved nanorod−substrate adhesion is required.

Patterned photonic crystals with structural colors on textile substrates have attracted a special attention due to the great advantages in application, which currently become a research hot-spot. This study utilized an ink-jet printing technology to prepare high-quality photonic crystal patterns with structural colors on polyester substrates. The self-assembly temperature of poly(styrene-N-methylol acrylamide) (P(St-NMA)) microspheres set to construct photonic crystals were deeply optimized. Moreover, the structural colors of prepared photonic crystal patterns were characterized and evaluated. When the mass fraction of P(St-NMA) microspheres was 1.0 wt.%, the pH value ranged from 5 to 7, and the surface tension was in the range of 63.79 to 71.20 mN/m, inks could present the best print performance. At 60 °C, prepared P(St-NMA) microsphere inks were good for printing to obtain patterned photonic crystals with regular arrangement and beautiful structural colors. Specifically, photonic crystals with different colors could be constructed by regulating the diameter of microspheres in inks, and prepared structural colors exhibited distinct iridescent phenomenon. The present results could provide a theoretical basis for the industrial realization of patterned photonic crystals by ink-jet printing technology.

Rearward amplification (RA) is an effective indicator of lateral stability for multi-trailer articulated heavy vehicles (MTAHVs). The International Organization for Standardization released the test manoeuvres, ISO-14791, for determining the indicator for MTAHVs. ISO-14791 recommends three methods, including two time-domain and one frequency-domain, to derive the RA measures. It was reported that the results from the three methods were not in good agreement. To explore this inconsistency among these methods, a multiple cycle sine-wave steering input (MCSSI) manoeuvre was simulated to obtain steady-state responses of MTAHVs. Furthermore, an automated frequency response method (AFRM) was used to derive the measures in the frequency-domain. This paper presents simulation results based on an A-Train Double. Results demonstrate that the steady-state RA measures under a MCSSI manoeuvre are in excellent agreement with those from frequency-domain methods. It is revealed that driver's steering behaviours impose a non-negligible impact on the transient RA measures of MTAHVs.

In a steering process, the steering-motor of a steer-by-wire (SBW) vehicle consumes energy. To facilitate energy efficiency analyses, the steeringmotor energy consumption is split into two parts, which correspond to varied and constant steering-wheel angle operating condition, respectively. The former condition is a vehicle operational manoeuvre, in which steering-wheel angle varies continuously, whereas the latter is a constant-radius circular-curve negotiation, in which steering-wheel angle maintains constant. Analysing the relation of steering-wheel angle with a road curvature, we propose an energysaving strategy for steering-motors of SBW vehicles. The energy-saving strategy is featured with a concept, a hydro-mechanical locking device, and an SBW controller for the steering-motor unit. The feasibility and effectiveness of the energy-saving strategy is demonstrated using closed-loop simulations. To implement the closed-loop simulation, we combine the driver, vehicle, and curved road models generated in CarSim software with the steering-motor model and the SBW controller developed in Matlab/Simulink.

This paper reviews the state-of-the-art control schemes for enhancing the lateral stability of car-trailer (CT) combinations. Various studies have been conducted on lateral stability control of single-unit vehicles, e.g., cars. However, much less attention has been paid to lateral stability control of multi-unit vehicles, e.g., CT, which usually exhibit poor manoeuvrability in curved-path negotiations and low lateral stability under high-speed evasive manoeuvres. The low lateral stability may lead to unstable motion modes, e.g., trailer-sway and jackknifing, causing severe accidents. To improve the lateral stability, various control schemes were designed considering relevant performance measures and evaluated using either numerical simulations or testing methods. Thus, the topics surveyed in this paper include: directional performance measures, evaluation methods, important parameters affecting the directional performance, and active control approaches for CT combinations. Important control schemes are emphasised and their features discussed and analysed. As a result of the overview, future research efforts are identified.

Hou et al. constructed tumor intracellular microenvironment responsive ZnFe2O4nanoparticles loading low‐dose paclitaxel (PTX) which encapsulated with cancer cell membrane (CCM)(ZnFe2O4‐PTX@CCM). ZnFe2O4‐PTX@CCM could release Fe3+, Zn2+and PTX in the tumor cytoplasm by responding to the high level of GSH, and thus stimulate anti‐tumor immunity by enhancing the cGAS/STING pathway.

The cyclic guanosine monophosphate‐adenosine monophosphate synthase (cGAS)/stimulator of interferon genes (STING) signalling pathway has been a promising target for anticancer immunity, but rationally activating and enhancing this pathway in tumour cells is critical. Herein, a glutathione sensitive ZnFe2O4‐based nanosystem is developed to programmatically initiate and enhance the STING signalling pathway in tumour cells. The prepared ZnFe2O4nanoparticles were coated with cancer cell membrane (CCM), which enabled the nanosystem target tumour cells. In tumour cells, ZnFe2O4nanoparticles could be disintegrated by responding to high level glutathione, and the released Fe3+generated reactive oxygen species to induce the DNA leakage into the cytoplasm to stimulate cGAS. Then Zn2+promoted cGAS‐DNA phase separation to intensify the cGAS enzymatic activity. In addition, the low dose encapsulation of paclitaxel (PTX) acting as an antimitotic agent (ZnFe2O4‐PTX@CCM) ensured the sustained activation of cGAS/STING pathway. The in vitro and in vivo results confirmed that ZnFe2O4‐PTX@CCM elevated the cGAS/STING activity, promoted dendritic cell maturation, increased cytotoxic T lymphocyte and natural killer cells infiltration, eventually inhibiting the tumour progress and postoperative recurrence. This study provided feasible references on constructing STING activation nanosystem for tumour immunotherapy. Tailor‐designed ZnFe2O4‐based nanosystem can respond to the tumour microenvironment and stimulate anti‐tumour immune responses by enhancing the cGAS/STING pathway. Moreover, it remodels immunosuppressive microenvironment, and effectively inhibits tumour growth as well as postoperative recurrence.

This paper examines the robustness of different controllers for active steering systems (ASSs) of articulated heavy vehicles (AHVs) in terms of the directional performance. Controllers based on the linear quadratic regulator (LQR) technique were designed for ASSs. The success of the LQR-based controllers is dependent on the accuracy of linear models for AHVs. When designing ASS controllers, linearisation of the AHV models is usually necessary; this results in model inaccuracy and un-modelled dynamics, and the robustness of the LQR-based controllers may be degraded. ASSs for AHVs are assessed in the time-domain, which may lead to an incomplete performance evaluation. This paper assesses the robustness of the ASS controllers designed with the techniques of sliding mode control (SMC), nonlinear sliding mode control (NSMC), and mu-synthesis (MS). The ASS controllers are evaluated using numerical simulation in terms of the trade-off between the manoeuvrability and the lateral stability at high speeds.

This paper presents an evaluation of control strategies for improving the lateral stability of car-trailer systems. A linear stability analysis method is proposed for the evaluation. The strategies include active trailer differential braking, active trailer steering and variable geometry approach. A linear 3 degrees of freedom (DOF) yaw-plane car-trailer model is generated for the controllers' design and a nonlinear 21-DOF yaw-roll car-trailer model is developed in CarSim to validate the stability control strategies by means of numerical simulations. To determine the stable motion boundary, eigenvalue analysis is conducted for identifying the vehicle critical speed. The linear quadratic regulator technique is applied to the design of controllers for active trailer braking, active trailer steering and variable geometry strategies. It is revealed that the active trailer braking strategy is feasible and effective for improving the lateral stability of car-trailer systems. Simulation results demonstrate the effectiveness of the linear stability analysis method.

Metal organic frameworks (MOFs) have recently attracted great attentions for the thermoelectric (TE) applications, owing to their intrinsic low thermal conductivity, but their TE efficiencies are still low due to the poor electronic transport properties. Various synthetic strategies have been designed to optimize the electronic properties of MOFs. Using a series of first principle calculations and band theory, we explore the effect of structural topology and redox matching between the metal and coordinated atoms on the TE transport properties. The presented results provide a fundamental guidance for optimizing electronic charge transport of existing MOFs, and for designing yet to be discovered conductive MOFs for thermoelectric applications.

This paper presents a design synthesis framework for directional performance optimization of multi-trailer articulated heavy vehicles with trailer lateral dynamic control systems, e.g. active trailer steering, trailer differential braking, active roll control or the coordination of the three systems. In order to demonstrate the effectiveness of the proposed framework, it was applied to the design optimization of a multi-trailer articulated heavy vehicle with an active trailer steering controller. In the design, a set of lateral stability measures is originally defined, and the design problem under simulated test manoeuvres is implemented using a parallel computing technique. It is illustrated that the proposed framework and the performance measures can be used to identify effectively the desired variables and to predict reliably the performance envelopes of multi-trailer articulated heavy vehicles with active safety systems by considering the concept of driver-adaptive-vehicle design.

Metal organic frameworks (MOFs) have recently attracted great attention for the thermoelectric (TE) applications, owing to their intrinsic low thermal conductivity, but their TE efficiencies are still low due to the poor electronic transport properties. Various synthetic strategies have been designed to optimize the electronic properties of MOFs. Using a series of first-principles calculations and band theory, we explore two effects on the TE transport properties: 1) structural topology and 2) redox matching between the metal and coordinated atoms. The results provide fundamental guidance for optimizing electronic charge transport of existing MOFs, and for designing yet-to-be-discovered conductive MOFs for thermoelectric applications.

This paper examines an active rear split spoiler designed for improving lateral stability of high-speed vehicles under high lateral acceleration (high-g) scenarios, such as a tight cornering manoeuvre at high speeds. Downforces produced by the spoiler can enhance the lateral stability of the vehicle under a high-g cornering manoeuvre. On the other hand, the spoiler may introduce additional drags on the vehicle. Aerodynamic analysis and wind tunnel testing are conducted to evaluate the dynamic effects of the active spoiler on a high-speed car. The downforce and drag, as well as their relationship, are investigated using CFD simulations of the car with the active rear split spoiler at different spoiler angles of attack and at different speeds. Then, the achieved CFD simulation results are compared with the experimental data derived from the wind tunnel on the physical car and the spoiler prototype. The observations and findings achieved from the study may provide valuable guidelines for developing active aerodynamic control systems to increase safety of high-speed vehicles.

This paper presents an optimal robust controller for active trailer differential braking (ATDB) systems of car-trailer (CT) combinations. To design ATDB systems, controllers based on the linear quadratic regulator (LQR) technique have been explored. In these LQR controller designs, vehicle forward speed, trailer payload, etc., were assumed as constants. In reality, a CT combination is frequently confronted with variations of operating conditions and vehicle parameters, which may impose significant impacts on the lateral stability of these vehicles. This motivates the investigation into robust controller designs. An ATDB controller is designed using the µ synthesis technique. A new method using a genetic algorithm (GA) for tuning the weighting function parameters for the robust controller is presented. In the parameters tuning process, the lateral stability is emphasised and the path-following capability is considered. Simulation results confirm the validity of the ATDB controller.

This paper provides valuable guidelines on the selection of dynamic vehicle models for control algorithm development, design optimization and linear stability analysis for multi-trailer articulated heavy vehicles with active safety systems. The validation of yaw-plane and yaw–roll models of a tractor–two-semitrailer combination using the TruckSim software package is presented in this paper. A linear four-degree-of-freedom yaw-plane model and a linear seven-degree-of-freedom yaw–roll model of the vehicle were generated, compared and evaluated. The linear models of the multi-trailer articulated heavy vehicle yield numerical simulation results which are validated by comparing with those obtained from the corresponding non-linear TruckSim model. This paper also includes eigenvalue and frequency-response analysis of the linear models to estimate the unstable motion modes and to predict the unique dynamic features of the multi-trailer articulated heavy vehicle in the frequency domain. A benchmark investigation of the models was performed to examine the fidelity, the complexity and the applicability of the linear models.

This paper presents a design validation method for active trailer steering (ATS) for improving low-speed manoeuvrability of multi-trailer articulated heavy vehicles (MTAHVs) using driver-hardware/software-in-the-loop (DH/SIL) simulations. A numerical-optimisation-based design of a MTAHV with ATS was reported. The ATS is featured with two controllers, one for improving the manoeuvrability and the other for enhancing the stability. To validate the design for minimising the path-following off-tracking (PFOT), real-time simulations are conducted on a DH/SIL platform fabricated by combining a vehicle simulator with two physical ATS axles. The PFOT controller is reconstructed and integrated with the real-time MTAHV model for DH/SIL simulations. A benchmark is performed for three designs: 1) without the PFOT controller and the physical ATS axles; 2) only with the PFOT controller; 3) with both the PFOT controller and the ATS axles. The benchmark validates the reported design and demonstrates the effectiveness of the proposed design validation method.

This paper proposes the application of an automated frequency response measuring (AFRM) technique to the lateral dynamic analysis in the frequency-domain for articulated heavy vehicles (AHVs). The AFRM method can be used to automatically acquire the frequency response function of the rearward amplification (RWA) ratio, an important performance measure of the lateral stability of AHVs. A numerical simulation in the time-domain can only achieve the corresponding dynamic response at a specified frequency; to achieve dynamic responses over a frequency band, numerous simulations at various frequencies have to be conducted, and this is a tedious and time consuming process. The RWA measure is frequency-dependent, and the measure in the frequency-domain is of critical importance for the stability evaluation and design synthesis of AHVs. The feasibility and effectiveness of the proposed method is examined using numerical simulations of a tractor/semitrailer combination represented by a linear and a nonlinear AHV model.

AbstractSalmonellais the most common cause of bacterial food poisoning in humans worldwide. Thus, rapid and reliable methods for the detection of this pathogen are required. Real-time reverse-transcriptase polymerase chain reaction (rt-RT-PCR), which detects the presence of mRNA (shorter half-life than DNA) has shown great potential for detecting viable pathogens. We recently identified a few new potential specific DNA sequences for Salmonella entericausing a comparative genomics method (Chen et al., 2010). In the present study, we examined the expression of the Salmonella-specific sigDEoperon (encoding invasion proteins within the pathogenicity island 5) under typical growth conditions to determine whether sigDEcould be a useful viability marker for the bacterium. We then assayed sigDEmRNA from cells heat-treated at 60°C, 100°C, and 121°C (autoclaved), and found that mRNA was degraded in autoclaved bacterial samples. These results showed that the sigDEtranscript is a suitable mRNA target for rt-RT-PCR with samples pretreated at 121°C. Thus, an rt-RT-PCR using sigDEprimers was developed for the detection of viable Salmonella. An RNA internal amplification control was constructed by overlap extension PCR, synthesized using in vitrotranscription with a T7 RNA polymerase promoter, and incorporated into the rt-RT-PCR system to eliminate false-negative results. The rt-RT-PCR system has the capability of specifically detecting all the tested S. entericaserovars, and the detection limit of this assay with cultures of SalmonellaTyphimurium ATCC 13311 was 101colony-forming units (CFU)/mL. After 18-h enrichment, sigDE-based rt-RT-PCR could detect as low as 100CFU/mL of Salmonellafrom egg broth and milk.

This paper presents the design for an active trailer-steering system of multi-trailer articulated heavy vehicles using driver-software-in-the-loop real-time simulations. A linear yaw-plane multi-trailer articulated heavy-vehicle model is generated to derive an optimal active trailer-steering controller. Then, the controller is reconstructed in LabVIEW and integrated with a vehicle model for a tractor– double-trailer combination developed in TruckSim. The driver-software-in-the-loop real-time simulations are conducted on a vehicle simulator. The driver-software-in-the-loop real-time simulations indicate that the active trailer-steering controller can effectively improve the low-speed manoeuvrability and high-speed stability of the multi-trailer articulated heavy vehicle when testing using a low-speed 360° roundabout path-following manoeuvre and a high-speed single-lane-change manoeuvre respectively. The investigation based on the driver-software-in-the-loop real-time simulations paves the way to future development of electronic control units for the active trailer-steering system using driver-hardware-in-the-loop real-time simulations.

This paper presents an automated design synthesis method for multi-trailer articulated heavy vehicles (MTAHVs) to coordinate the trade-off between the manoeuvrability and stability. Conventionally, the design synthesis of MTAHVs is based on trial and error approaches. This is difficult, time-consuming and tedious. To tackle this problem, a design method is proposed. The method has the following features: 1) vehicle modelling, performance evaluation, and design selection are implemented by computers; 2) a MTAHV model is introduced in the design optimisation; 3) in the closed-loop simulation, testing manoeuvres are emulated such that a driver model ‘drives’ the virtual MTAHV to follow a predefined trajectory. To test the method, the combination of a tractor and two semitrailers are optimised. It is indicated that the conflicting criteria of manoeuvrability and stability can be simultaneously improved. The approach may identify desired design variables and predict performance envelopes in early design stages of MTAHVs.

Optical reflection, transmission, and surface-enhanced Raman scattering (SERS) of L-shaped silver nanorod arrays with different lengths prepared by oblique angle deposition are studied and compared in detail to those properties of straight silver nanorod arrays. With the increase of the arm length of both the L-shaped and straight nanorods, the optical reflectance increases, but the transmittance decreases. The reflectance of L-shaped Ag nanorods is similar to that of straight nanorods with the same total length, but the transmittance is lower for the former than for the latter. Transfer matrix method for multilayer thin films based on anisotropic effective medium theory has been used to calculate the optical properties of both the L-shaped and straight Ag nanorod arrays, and the calculated results are qualitatively consistent with the experimental results. The SERS enhancement of the L-shaped and straight Ag nanorod arrays increases when the total arm length increases from 350 to 650 nm. The SERS behavior can be interpreted qualitatively by the thickness dependence of the optical absorbance effect.

We present molecular and lattice dynamics calculations of the thermal conductivity of nanoporous silicon, and we show that it may attain values 10−20 times smaller than in bulk Si for porosities and surface-to-volume ratios similar to those obtained in recently fabricated nanomeshes. Further reduction of almost an order of magnitude is obtained in thin films with thickness of 20 nm, in agreement with experiment. We show that the presence of pores has two main effects on heat carriers: appearance of non-propagating, diffusive modes and reduction of the group velocity of propagating modes. The former effect is enhanced by the presence of disorder at the pore surfaces, while the latter is enhanced by decreasing film thickness.

Silicon is a promising anode material for Li-ion batteries in regarding of high capacity, low cost and safety, but it suffers poor cycling stability due to the pulverization induced by severe volume expansion/shrinkage (297%) during lithium insertion/extraction. In our previous investigation on aluminum nanorods anodes, it is found the selection of substrates in which Al nanorods grown plays the significant role in prevention of pulverization resulting in the increase of cycling life [1]. Adapting this knowledge, we investigated the Si based nanorods by tuning its composition and element distribution. Our results show that the Si-Cu composite nanorods demonstrated sustainable capacity of 500 mAh/g in 100 cycles attributing to its flexible and less brittle nature.

Using a unique glancing angle co‐deposition technique, face‐centered cubic Ag nanoparticles have been embedded into aligned polycrystalline MgF2nanorods with different topological shapes, such as tilted, zigzag, vertical, and helical nanorods. The optical properties of the artificial nanocomposite materials, such as surface plasmon resonance and polarization absorbance, are determined by the size of the Ag nanoparticles as well as the alignment and shape of the MgF2nanorod arrays. The combination of co‐deposition and glancing angle deposition provides a unique way to design novel nanocomposite materials and doped nanorod arrays.

The structure and chromic properties of WO3·H2O nanoflakes have been investigated in situ by Raman spectroscopy and optical transmission under 785-nm laser irradiation with different powers. At a small power below 48 mW, the characteristic stretching vibrations of orthorhombic WO3·H2O at 1650 cm-1(W6−O) and 2947 cm-1(terminal W6−O) are observed, and their respective peak intensities, along with optical transmission, decay monotonically with irradiation time. At high-power irradiation (>48 mW), the Raman peaks at 1and 2decrease rapidly, and two new W6−O stretching vibrations at 3710 cm-1and 4805 cm-1, ascribed to monoclinic WO3, appear. At the same time, a photoinduced color change occurs rapidly, accompanied by a subsequent slow oxidation process, as reflected in optical transmission. The change of the Raman peaks' intensities with the irradiation time is consistent with the change of the optical transmission. Heat transfer analysis and the annealing experiment show that the color change is ascribed to photoinduced thermochromism, and a photothermal coloration reaction mechanism is proposed to explain quantitatively this near-infrared laser-induced effect.

Developing electrode materials with better storage performances is currently one of the hotspots in the field of battery storage. Though monolayer materials such as Ti2CS2and blue phosphorene (BlueP) monolayers have some excellent storage properties as anode materials, the re-stacking of Ti2CS2and poor conductivity of BlueP may limit their application prospects. Considering that the heterostructure may retain/avoid the advantages/disadvantages of monolayer anodes, we study the load and diffusion of Li/Na/K ions on a Ti2CS2/BlueP heterostructure to explore the feasibility of it as an anode via density functional theory. We find that this heterostructure not only retains the stability characteristics of Ti2CS2and the high capacity of BlueP but also avoids the re-stacking of Ti2CS2and poor conductivity of BlueP. Moreover, 4/8/3 layers (nine atoms per layer) of Li/Na/K are loaded into this heterostructure, far exceeding the 2/2/2 layers loaded into the pristine BlueP and 2/6/2.67 layers into the pristine Ti2CS2due to the interfacial synergy. In addition, the Ti2CS2/BlueP anode material shows high capacity (344–917 mA h/g), low average open-circuit voltage (OCV) (0.32–0.78 V), and low diffusion barrier (0.10–0.37 eV). Furthermore, Ti2CS2/BlueP presents better prospects for Na-ion batteries among three batteries owing to the highest capacity and lowest average OCV.

Solvothermal reaction of 4,4’,4’-nitrilotribenzoic acid (H3TCA) with Ca(NO3)2·4H2O and Cd(NO3)2·4H2O successfully afforded a heterometallic compound, that is, [Cd2Ca(TCA)2(DMA)2(H2O)3]n·2n(DMA) (1, DMA = N,N’-dimethylacetamide). The structure of 1 was further characterized through EA, diffraction of single crystal X-ray, and thermogravimetric analysis (TGA) together with powder X-ray diffraction (PXRD). Moreover, complex 1’s luminescent performance in solid state was also discussed at environmental temperature. The applications on the ischemic cerebral infarction therapy were evaluated, and the specific mechanism was investigated at the same time. Firstly, the hypersensitivity C-reactive protein (hs-CRP) content in human brain microvascular endothelial cell (HBMEC) was measured with real-time reverse transcription-polymerase chain reaction (RT-PCR). Then, interleukin-18 and interleukin-1β content released through the HBMEC was detected with enzyme-linked immunosorbent assay (ELISA).

An intriguing new class of two-dimensional (2D) materials based on metal–organic frameworks (MOFs) has recently been developed that displays electrical conductivity, a rarity among these nanoporous materials. The emergence of conducting MOFs raises questions about their fundamental electronic properties, but few studies exist in this regard. Here, we present an integrated theory and experimental investigation to probe the effects of metal substitution on the charge transport properties of M-HITP, where M = Ni or Pt and HITP = 2,3,6,7,10,11-hexaiminotriphenylene. The results show that the identity of the M-HITP majority charge carrier can be changed without intentional introduction of electronically active dopants. We observe that the selection of the metal ion substantially affects charge transport. Using the known structure, Ni-HITP, we synthesized a new amorphous material, a-Pt-HITP, which although amorphous is nevertheless found to be porous upon desolvation. Importantly, this new material exhibits p-type charge transport behavior, unlike Ni-HITP, which displays n-type charge transport. These results demonstrate that both p- and n-type materials can be achieved within the same MOF topology through appropriate choice of the metal ion.

We designed MoS2/M2CS2(M = Ti, V) heterostructures and investigated their electrochemical performances to evaluate their possibility to serve as anode materials for metal (Li/Na/K/Mg)-ion batteries (LIBs/NIBs/KIBs/MIBs) by the first-principles method. The results show that the two heterostructures are stable and exhibit metallic properties before or after adsorption of metal ions. The low diffusion barriers (below 0.4 eV) indicate that the two heterostructures have excellent rate performances for the four batteries. The theoretical capacities of heterostructures for NIBs (about 400 mAh/g) or LIBs (about 320 mAh/g) are all much higher than those for KIBs or MIBs. This demonstrates that MoS2/M2CS2are suitable as anode materials for NIBs/LIBs instead of KIBs/MIBs. Furthermore, the average open-circuit voltages of MoS2/M2CS2for NIBs are both lower than those for LIBs, and they show higher capacities for NIBs than LIBs, which further manifest that the MoS2/M2CS2heterostructures are more promising candidates for NIBs.

This article mainly considers the problem of trajectory tracking control problem of quad-rotor system with velocity constrain under the consideration of safety. A model-based nonlinear controller is proposed which can guarantee not only the asymptotical stability for control system but also the velocity under a safe range. Firstly, based on backstepping design, a position tracking controller with velocity constraint is proposed to ensure that the desired position can be tracked with velocity constrains. At the second step, considering attitude subsystem, an attitude controller is proposed to improve the attitude dynamic response performance. Finally, the validity and superiority of the design has been verified in simulation results.

Gear–wheelset system is a crucial substructure in railway vehicles which affects the operation safety and system reliability, especially in the process of traction and braking conditions. Unlike the general gear transmission system, the gear–wheelset system of railway vehicles operates under an environment with several nonsmooth factors; therefore, it is necessary to analyze the nonsmooth dynamics of the gear–wheelset system for understanding dynamic characteristics better. Herein, a planar dynamic model of the gear–wheelset system of railway vehicles considering motor-driving torque, braking torque, wheel–rail nonlinear interaction forces, nonlinear meshing damping, and piecewise continuous time-varying meshing stiffness is proposed. Then, the proposed model is validated by a simpack model using wheelset's longitudinal velocity. Subsequently, two numerical simulations were performed to reveal the nonsmooth dynamic characteristics under traction and braking conditions. The simulation results indicate that the dynamic stationary point exists in nonsmooth dynamics under traction and braking conditions, which is a critical boundary for transiting any state to a dynamic equilibrium. Besides, the results exhibit the inseparable relationship between time-frequency dynamic characteristics, slip velocity, and wheel–rail nonlinear interaction forces. The effects of harmonic torque under traction conditions and compound braking behavior under braking conditions significantly affect these dynamic characteristics. Additionally, sufficient driving torque can increase the proportion of forward contact and improve the smoothness of the rotation, and the intermittent gear contact phenomenon occurs alternately and frequently in the traction condition. Conversely, only reverse contact occurs in the braking condition.

Metal organic frameworks (MOFs) have recently attracted great attentions for the thermoelectric (TE) applications, owing to their intrinsic low thermal conductivity, but their TE efficiencies are still low due to the poor electronic transport properties. Various synthetic strategies have been designed to optimize the electronic properties of MOFs. Using a series of first principle calculations and band theory, we explore the effect of structural topology and redox matching between the metal and coordinated atoms on the TE transport properties. The presented results provide a fundamental guidance for optimizing electronic charge transport of existing MOFs, and for designing yet to be discovered conductive MOFs for thermoelectric applications.

Metal organic frameworks (MOFs) have recently attracted great attention for the thermoelectric (TE) applications, owing to their intrinsic low thermal conductivity, but their TE efficiencies are still low due to the poor electronic transport properties. Various synthetic strategies have been designed to optimize the electronic properties of MOFs. Using a series of first-principles calculations and band theory, we explore two effects on the TE transport properties: 1) structural topology and 2) redox matching between the metal and coordinated atoms. The results provide fundamental guidance for optimizing electronic charge transport of existing MOFs, and for designing yet-to-be-discovered conductive MOFs for thermoelectric applications.

Selenium nanowires have been synthesized by using 2-mercaptoethylamine-depleted CdSe nanoparticles as selenium source and ethylenediaminetetramethylenephosphonic acid as chelating agent. The products were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and UV–vis spectrophotometry. The result shows that the selenium nanowires are single crystals grown along the [001] direction of hexagonal lattice. The optical measurement shows a blue shift relative to the bulk hexagonal selenium, and the optical bandedge might be attributed to the interchain interactions within a hexagonal selenium crystal.

Silicon is a promising anode material for Li-ion batteries in regarding of high capacity, low cost and safety, but it suffers poor cycling stability due to the pulverization induced by severe volume expansion/shrinkage (297%) during lithium insertion/extraction. In our previous investigation on aluminum nanorods anodes, it is found the selection of substrates in which Al nanorods grown plays the significant role in prevention of pulverization resulting in the increase of cycling life [1]. Adapting this knowledge, we investigated the Si based nanorods by tuning its composition and element distribution. Our results show that the Si-Cu composite nanorods demonstrated sustainable capacity of 500 mAh/g in 100 cycles attributing to its flexible and less brittle nature.