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[Display omitted] • MOF-303-derived Pd@KNDC(10-900) catalyst with highly dispersed Pd NPs was prepared. • The mesopores of Pd@KNDC(10-900) catalyst can promote mass transfer and increase accessibility. • The N sites on the KNDC(900) support could improve the dispersion and reduce the particle size of the Pd active NPs. • The ultrasmall size (4.1 nm) and high dispersion of Pd NPs could expose more catalytic active sites. • The Pd@KNDC(10-900) catalyst presents an initial TOF value of 2215 h−1, 100 % FA conversion and H 2 selectivity, and excellent stability at 50 °C. In this work, ultrasmall Pd nanoparticles (NPs) with a mean size of 4.1 nm immobilized by the MOF-303-derived N-doped carbon (NDC) have been prepared for efficient formic acid (FA) dehydrogenation. The optimized catalyst Pd@KNDC(10-900) showed the extraordinary catalytic activity, and the initial turnover frequency (TOF) value is 2215 h−1 at 50 °C, accompanied by 100 % FA conversion and H 2 selectivity, facilitated by the incorporation of sodium formate (SF) as an additive. Moreover, the Pd@KNDC(10-900) could maintain an outstanding stability enduring through five successive runs with only a marginal reduction in activity. The robust synergistic interactions between Pd NPs and N sites on the KNDC(900) together with the ultrafine size and high dispersion of Pd NPs as the catalytic active sites are responsible for the superior catalytic performance. This work will provide a new paradigm by using the MOF-derived NDC supports for the construction of Pd-based catalysts for FA dehydrogenation. [ABSTRACT FROM AUTHOR]

• A coupled oscillatory element is proposed for interface planar crack. • A general numerical method for solving interface planar crack is established. • It is proved that all K 1 , K 2 and K 3 are related to two parameters ε and γ. • K 1 , K 2 and K 3 are given for interface elliptical crack under uniform tension. This paper studies the stress intensity factors and their correlations with bimaterial parameters for the interface planar cracks by hypersingular integral equations. A new bimaterial parameter γ is defined, and the correlations of the stress intensity factors of interface planar crack with two parameters ε and γ are proved. The relative displacement fundamental function is proposed based on the crack's peripheral equation, thus one kind of element with coupled oscillatory characteristic of mode-1 and mode-2 is established for the interface planar crack. For the interface elliptical cracks with b/a = 0.2, 0.4, 0.6, 0.8, 1.0, the stress intensity factors along the crack front are calculated by solving the hypersingular integral equations. Comparison with the existing exact solutions show that the numerical results have a high accuracy. For the interface planar cracks under tensile load, there exist K 1 , K 2 and K 3 at the same time. The numerical results show that K 1 is very weakly related to ε and γ, K 2 strongly to ε and weakly to γ, and K 3 shows a significant correlation with both parameters ε and γ. K 3 is much smaller than K 1 and K 2 and can be ignored in fracture analysis of problems with remote mode-1 loading. [ABSTRACT FROM AUTHOR]

Unsafe acts at non-signalized intersections have become a primary contributor to traffic accidents and fatalities. Whereas many studies have focused on non-signalized intersections in the past decade, capturing and recording road users' micro-behavior and risk in the mixed traffic flow remain challenging. A large number of two-wheelers (e.g., bicycles and e-bikes) appear at non-signalized intersections, in which the conflict behaviors are highly unpredictable. In this study, conflicts involving two-wheelers and cars at non-signalized intersections were investigated based on trajectory data collected with a YOLOv3-based framework automatically. A novel conflict identification algorithm was developed to gather and process microscopic trajectory data. To detect conflict behaviors involving two-wheelers and cars, near-crash identification was employed with a post-encroachment time indicator that also contributes to demonstrating the effect of vehicle order on conflict severity from an unprecedented perspective. The proposed framework was applied to a case study at a university campus in Shanghai. To explore the relationship between contributing factors and conflict severity, a significance test and ordered probability models were implemented using 10,304 conflicts collected from video data. The statistical analysis disclosed that conflicts involving e-bikes accounted for the highest proportion, and the order of vehicles (e.g., pre-encroachment vehicle and post-encroachment vehicle) has different effects on conflict severity. The analytical results with risk assessment can contribute to developing intersection-specific countermeasures for traffic safety from the perspectives of education, engineering, and law enforcement. The trajectory-based framework can be adapted to intelligent transportation systems to enhance safety management. [ABSTRACT FROM AUTHOR]

Some studies suggest that women with primary dysmenorrhea have distinct emotional or personality features. For example, they might exaggerate their responses to external stimuli, such as to intensity-increasing auditory stimuli. Fifteen women with primary dysmenorrhea and 15 healthy women were invited to undergo tests of the intensity dependence of auditory evoked potentials (IDAEP), the Functional and Emotional Measure of Dysmenorrhea, and the Plutchik-van Praag Depression Inventory. Study participants with dysmenorrhea showed higher Functional and Emotional scale scores and stronger IDAEP. Regarding the IDAEP generation, the source inversion of N1 and P2 disclosed the activated bilateral superior temporal gyri, medial and superior prefrontal gyri in all participants, and additionally, the middle frontal gyri in dysmenorrhea patients. We report a pronounced IDAEP in primary dysmenorrhea, which indicates the decreased cerebral serotonergic innervations and points to increased activations in the prefrontal and frontal areas in the disorder.Perspective: Using an IDAEP technique, the authors found decreased serotonergic innervation and altered cerebral activation in women with primary dysmenorrhea, which might offer some pharmacotherapeutic clues for the disorder. [ABSTRACT FROM AUTHOR]

• COVID-19-caused resilience performance of metro rails was evaluated quantitatively. • Key characteristics of responses to the disturbance were modeled with multivariate multiple regression. • The applicability and rationality of developed models were validated with U.S. metro data. The metro rail system has proven to be the most efficient high-capacity carriers. During the unprecedented coronavirus disease 2019 (COVID-19) challenge, non-pharmaceutical interventions become a widely adopted strategy to limit physical movements and interactions. For situational awareness and decision support, data-driven analytics about serviceability are invaluable to metro agencies and decision-makers of cities. This paper presents a data-driven analytical framework that quantitatively evaluates COVID-19-caused resilience performance of metro rails. Several characteristics (e.g., vulnerability, robustness, rapidity, and degree to return) of the metro system's responses to the disturbance were identified and modeled with multivariate multiple regression. The applicability and rationality of the resilience evaluation model were validated by the metro transit data of the United States. The preliminary results disclosed that metro rail transit encountered more vulnerability (90.6%) in passenger trips than motorbus and light rail (around 70%). A set of statistical models were employed to disentangle the effect of socio-demographic variables and COVID-19-related factors on the metro transit. The disclosed emerging knowledge of resilience provides an in-depth understanding of mobility trends for the public and time-sensitive decision support for the policy effects, to further improve the service and management of the metro system under the spread of the epidemic. [ABSTRACT FROM AUTHOR]

• Differences between bicycle and e-bike were investigated. • Latent variables and interrelationships were measured with structural equation modeling. • E-bikes' decision-making capacity is affected by infrastructure quality. • The need for differentiated development of cycling safety was highlighted. As common transportation modes at non-signalized intersections, bicycles and e-bikes have been involved in most traffic crashes. Although a large number of studies have been dedicated to studying the safety problems caused by bicycles and e-bikes, there is still limited attention paid to the differences between them, especially at non-signalized intersections. This paper compares the differences between bicycles and e-bikes based on a self-administered questionnaire. This questionnaire was distributed to bicycle users (N = 453) and e-bike users (N = 439). The personal characteristics, decision-making capacity, the feeling of infrastructure, perceived level of service, and perceived level of risk were adopted as the performance indicators to depict the difference in the study area. Using statistical methodologies and the Structural Equation Model (SEM), key findings indicate that perceived level of service was found to be significantly different between bicycles and e-bikes at most non-signalized intersections. 43.4 % of e-bike riders often or always choose to avoid riding under extreme weather, while 58.7 % of bicycle riders avoid riding under extreme weather. Moreover, compared with bicycles, e-bikes' decision-making capacity is affected more by infrastructure quality. The difference between bicycles and e-bikes highlights the need for differentiated development of cycling safety education and law enforcement. [ABSTRACT FROM AUTHOR]

Abstract: Studies between disordered personality and the Big-Five or the Alternative Five-Factor model of normal personality have consistently shown four higher traits. The fifth higher trait, relating to Openness to Experience or Impulsive Sensation Seeking was less supported. The culture-free Nonverbal Personality Questionnaire (NPQ) might help us to characterise the fifth higher trait. We therefore tried the Dimensional Assessment of Personality Pathology (DAPP), the NEO-Personality Inventory-Revised (NEO-PI-R), the Zuckerman–Kuhlman Personality Questionnaire (ZKPQ) and the NPQ in 253 healthy participants. Our results yielded five factors, four of which resembled the previous ones. The fifth one, namely Peculiarity Seeking, was defined by NPQ and NEO-PI-R Openness to Experience, ZKPQ Impulsive Sensation Seeking and DAPP Stimulus Seeking. Whether the fifth factor is linked to the schizotypal personality disorder as proposed remains unanswered. [Copyright &y& Elsevier]

Abstract: Objective: To study the contribution of executive function to abnormal recognition of facial expressions of emotion in schizophrenia patients. Methods: Abnormal recognition of facial expressions of emotion was assayed according to Japanese and Caucasian facial expressions of emotion (JACFEE), Wisconsin card sorting test (WCST), positive and negative symptom scale, and Hamilton anxiety and depression scale, respectively, in 88 paranoid schizophrenia patients and 75 healthy volunteers. Results: Patients scored higher on the Positive and Negative Symptom Scale and the Hamilton Anxiety and Depression Scales, displayed lower JACFEE recognition accuracies and poorer WCST performances. The JACFEE recognition accuracy of contempt and disgust was negatively correlated with the negative symptom scale score while the recognition accuracy of fear was positively with the positive symptom scale score and the recognition accuracy of surprise was negatively with the general psychopathology score in patients. Moreover, the WCST could predict the JACFEE recognition accuracy of contempt, disgust, and sadness in patients, and the perseverative errors negatively predicted the recognition accuracy of sadness in healthy volunteers. The JACFEE recognition accuracy of sadness could predict the WCST categories in paranoid schizophrenia patients. Conclusion: Recognition accuracy of social-/moral emotions, such as contempt, disgust and sadness is related to the executive function in paranoid schizophrenia patients, especially when regarding sadness. [Copyright &y& Elsevier]

Abstract: Background: Processing facial expressions of emotion is deteriorated in depression, which might be more pronounced in treatment-resistant depression (TRD), especially when the latter is comorbid with borderline personality disorder (BPD). Neurophysiologically, both early perceptual and late cognitive cerebral processes of facial emotions can be illustrated by event-related potentials (ERPs). Methods: We therefore tried the ERPs to facial expressions of Neutral, Anger, Happiness, and Sadness in 25 patients with TRD, 15 with BPD, 22 with their comorbidity (TRD+BPD), as well as in 37 healthy volunteers. The depression levels of participants were measured with the Plutchik–van Praag Depressive Inventory (PVP). Results: There was no group difference regarding either N1 (N170), P2, N2, P3a or P3b latency or amplitude to the four facial emotions. Reaction times (RTs) to Anger (p <.01), Happiness (p <.01), and Sadness (p <.001) in TRD, and those to Anger (p <.01) and Happiness (p <.01) in TRD+BPD patients were longer than those in the healthy volunteers. RTs to the four facial expressions were positively correlated (p <.01) with their depressive moods in all participants. In addition, PVP was positively correlated with the P2 latency to Anger in TRD+BPD patients (Fz, p <.01; Cz, p <.01; Pz, p <.01). Conclusions: BPD contributed little to TRD or TRD+BPD regarding cerebral processing of facial emotions, however, other cognitive and behavioral data suggest a generalized impairment when responding to facial emotions in TRD and TRD+BPD patients, and a deteriorated perceptual processing of Anger in TRD+BPD patients. [Copyright &y& Elsevier]

Abstract: Objective: Cognitive dysfunctions, such as attentional impairment, are central features of both treatment-resistant depression (TRD) and borderline personality disorder (BPD). The treatment failure of TRD due to its comorbidity with BPD is debated in the literature. The mismatch negativity (MMN) of the event-related potentials provides an objective marker of involuntary stimulus selective processing, which might help shed light on this issue and provide an avenue for investigating a possible endophenotypic marker for TRD. Method: We investigated MMN in 22 patients with TRD, 19 with BPD, and 22 with TRD cormorbid with BPD (TRD+BPD), as well as in 32 healthy volunteers, by employing an acoustic frequency deviance paradigm. In addition, we measured the depressive mood using the Plutchik–van Praag (PVP) depression inventory. Results: There was no significant between-group difference for the N1 latencies/amplitudes, both to the standard and deviant stimuli, and no significant between-group difference for MMN latencies. However, MMN amplitudes were higher in the TRD group than those in the other three groups. PVP scores were highest in TRD+BPD, then TRD, BPD patients, and lowest in healthy subjects. The higher MMN was not correlated with PVP score, nor with the duration of life-long depression, which can be considered as a neurophysiological marker for TRD. Conclusion: An atypical lack of inhibition on the irrelevant stimuli or increased cortical neuronal activity, especially frontal area, or both, might be responsible for the finding. [Copyright &y& Elsevier]

Abstract: An organic UV absorbent has been intercalated into a layered double hydroxide (LDH) host by ion exchange of a Zn–Al–LDH-nitrate precursor with a solution of 2,3-dihydroxynaphthalene-6-sulfonic acid (DNSA) sodium salt in water. After intercalation of the UV absorbent, the powder X-ray diffraction (XRD) pattern shows that the interlayer distance in the LDHs increases from 0.90 to 1.59 nm. The possible structure is that the interlayer DNSA anions arrange in a monolayer and in a perpendicular orientation toward the hydroxide layers. Infrared spectra and TG–DTA curves reveal the presence of a complex system of supramolecular host–guest interactions between layers. The thermal stability of the intercalated UV absorbent was investigated by TG–DTA and it was found that this material is more stable than the original organic UV absorbent at high temperature, showing that the thermostability is markedly enhanced after intercalation into the LDH host. The UV absorbent-intercalated LDHs exhibit excellent UV photostability in polypropylene composites. [Copyright &y& Elsevier]

Mimicry of the somatosensory system in the human skin via electronic devices exhibits broad applications in intelligent robotics and wearable electronics. Here, we report a novel biomimetic flexible dual-mode pressure sensor that is based on the interlocked piezoelectric and piezoresistive films with pyramid microstructures. The sensitivity of the sensor is significantly enhanced because of the induced larger stain variation along the thickness direction of the former piezoelectric film and increased contact area in the latter piezoresistive film. The synergistic effect of the piezoelectric and piezoresistive responses to stimuli also allows the dual-mode sensor to detect over broad pressure and frequency ranges. The analysis of these signals can deconvolute multiple aspects of the complex stimuli loading processes, including their loading direction, rate, magnitude, and duration. As a proof-of-concept demonstration, the dual-mode pressure sensor is successfully integrated with manipulators and human bodies to decode the complex and delicate picking processes and human motions, respectively. When combined with the other sensing modalities, the multifunctional dual-mode pressure sensor delivers new application opportunities in intelligent soft robotics and human-machine interfaces. Image 1 • A biomimetic dual-mode pressure sensor that is based on the interlocked piezoelectric and piezoresistive films. • The synergistic effect allows the dual-mode sensor to exhibit a high sensitivity over a broad pressure and frequency range. • The dual-mode sensor deconvolutes the loading rate, magnitude, and direction of the complex loading process. • The application of the dual-mode sensor for human-machine interfaces demonstrates its capability to control the manipulator. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Pd 3 Co 2 /CeZrSBA-15-NH 2 catalyst with short channels and highly dispersed PdCo alloy NPs was prepared successfully. • The special short channels of Pd 3 Co 2 /CeZrSBA-15-NH 2 catalyst can promote mass transfer and increase accessibility. • The amine groups on the CeZrSBA-15-NH 2 could improve the dispersion and reduce the particle size of the PdCo active metals. • The ultrafine size (1.6 nm) and high dispersion of PdCo alloy NPs could expose more catalytic active sites. • The Pd 3 Co 2 /CeZrSBA-15-NH 2 presents a TOF of 2001 h−1, 100 % FA conversion and H 2 selectivity, and good stability at 323 K. The rational design of heterogeneous catalysts with remarkable activity and low cost is essential yet challenging for formic acid (HCOOH, FA) dehydrogenation. Herein, ultrafine bimetallic PdCo nanoparticles (NPs) dispersed on the amine-functionalized CeZrSBA-15 (CeZrSBA-15-NH 2) with short channels have been successfully prepared. The optimized catalyst Pd 3 Co 2 /CeZrSBA-15-NH 2 (the Pd/Co molar ratio is 3:2) displayed the extraordinary catalytic performance of FA dehydrogenation with 100 % FA conversion and H 2 selectivity. Furthermore, in the presence of sodium formate (SF) as an additive, the catalytic system achieved an impressive initial turnover frequency (TOF) of 2001 h−1 at a temperature of 323 K, which is better than the TM (transition metal)-containing Pd-based heterogeneous systems ever published under the similar reaction conditions. The exceptional catalytic activity is ascribed to several key factors, including the presence of short channels that facilitate the efficient transfer of reactants, the ultrafine size (1.6 nm) and uniform dispersion of PdCo nanoparticles, which serve as the active catalytic sites on the CeZrSBA-15-NH 2 support. Additionally, the regulated electronic effects induced by Pd and Co, coupled with the metal-support interaction (MSI) effect, further enhance the catalytic performance. This work affords a new paradigm into developing effective mesoporous silica-based heterogeneous catalysts for H 2 production from FA dehydrogenation. [ABSTRACT FROM AUTHOR]

Laser-assisted thermoplastic composite automated placement method has been applied to the molding of composites due to its advantages of fast molding speed and high heating efficiency. This study focuses on designing a robot for laser-assisted thermoplastic composite automated fiber placement, employing a modular approach to create a versatile fiber placement head. Control functions, such as electrical circuits, a computer interface, and tension control, were developed. Hybrid laminates, combining GF/PP unidirectional and braided composites, were manufactured by independently adjusting laser power (275 W–400 W) and compression force (150 N–400 N). Bonding properties were analyzed using wedge peel tests and microscopic detection, revealing superior toughness in laser-assisted laminates compared to autoclave counterparts. Altering laser power and compression force impacted polypropylene resin distribution, influencing hybrid interlayer peel strength. The inclusion of braided materials and elevated mold temperature proved effective in minimizing lamination warpage in GF/PP laminates. • The modular laser-assisted head for automated fiber placement is designed for rapid bonding of thermoplastic composites. • The peel strength of hybrid laminates made by laser-assisted placement was superior to those made by autoclave, which had better toughness. • Adding braided material increases laminate stiffness, reducing warpage during automated thermoplastic composite placement. [ABSTRACT FROM AUTHOR]

Cancer cells consume large amounts of glucose to produce lactate, even in the presence of ample oxygen. This phenomenon is known as the Warburg effect. The pyruvate kinase promotes aerobic glycolysis, and the pyruvate kinase M2 isoform (PKM2) is highly expressed in many cancer cells. Although the Warburg effect is a hallmark of cancer, the mechanism by which PKM2 contributes to the Warburg effect, and its role in tumor growth remain to be defined. We proposed that PKM2 activates transcription of hypoxia inducible factor-1α (HIF-1α) by phosphorylating STAT3 (signal transducer and activator of transcription 3) at Y705 (tyrosine 705) as a plausible mechanism for liver cancer cell proliferation. In the current study, we observed that PKM2 was over-expressed in hepatocellular carcinoma (HCC) tissues compared to adjacent normal tissues. The experiments further indicate that nuclear PKM2 is an active protein kinase in cultured cells. Knockdown of PKM2 affected the levels of HIF-1α and Bcl-xL (B-cell lymphoma-extra large), suggesting that PKM2 plays an important role in promoting cell proliferation. In conclusion, the current findings demonstrate that PKM2 is an active protein kinase, and promotes liver cancer cell proliferation by up-regulating HIF-1α and Bcl-xL expression. [ABSTRACT FROM AUTHOR]

• A bionic webbed foot flexible gripper with variable stiffness was designed. • A layer jamming skin was designed and fabrication as a key component of gripper. Inspired by webbed feet, a bionic webbed foot soft gripper with variable stiffness was designed by integrating a pneumatic networks actuator with layer jamming skin. Layer jamming skin as the key component of bionic webbed foot soft gripper, its design and fabrication process were described. An experimental platform combining stretch/bend control was established to analyze the impact of activated negative pressure, different materials and shapes jamming units, and the number of jamming layers on the stiffness of the layer jamming skin. The layer jamming skin conforms to the characteristics of variable stiffness by evaluating the experimental and numerical results of the layer jamming skin under external loading. The curling and adaptability test demonstrated the layer jamming skin's adaptability and flexibility to various shapes and sizes of caught objects. The variable stiffness, adaptability, and gripping force of the bionic webbed foot soft gripper during object grasping were assessed through gripping experiments. This work presents an enveloping gripper with variable stiffness, high adaptability, and strong grasping force. [ABSTRACT FROM AUTHOR]

• Chiral CNC-cyanidin films with multiple stimulus responses for freshness monitoring. • CNC and cyanidins are ecologically-friendly natural substances with no toxicity. • The samples with enhanced strength exhibit good flexibility under bended states. • CNC-cyanidin films displayed significant color variation over the pH range of 2–13. • The sample could be a convenient and visual diagnostic freshness monitor in real-time. Biobased multi-stimulation materials have received considerable attention for intelligent packaging and anti-counterfeiting applications. Cellulose nanocrystals (CNCs) and cyanidins are good material candidates for monitoring food freshness as they are eco-friendly natural substances. This work incorporated cyanidin with a CNC-hosting substrate to develop a simple, environment-friendly colorimetric device to visualize food freshness. Across the pH range of 2–13, the indicator exhibited noticeable color changes ranging from red to gray and eventually to orange. The CNC-cyanidin (CC) film exhibited a dramatic color change from blue to dark red and high sensitivity at a relative humidity of 30 %–100 %. In corresponding to the total volatile elemental nitrogen (TVB-N) level of shrimp, the indicator showed distinguishable colors at different stages of shrimp. The findings imply that the samples have substantial potential for use as an intelligent indicator for tracking shrimp freshness. [ABSTRACT FROM AUTHOR]

A multi-objective optimization technique for bistable laminates is proposed in the present study. Bistable laminates have wide application prospects as deployable structures of aerospace structures and wind turbines, but the design of their mechanical characteristics and configurations might be a hard job considering the conflicting requirements. Surrogate models of the bistable laminates are created by response surface method. The non-dominated sorting genetic algorithm-II (NSGA-Ⅱ) is used to obtain Pareto-optimal solution where the presence of a trade-off relation between the mechanical performances and configurations of bistable laminates has been established. The trigger forces of bistable laminates during snapping to another stable configuration are the mechanical objective functions, while the curvatures of their different stable configurations are used as the conflicting objective functions. And the relationship between different stable configurations is considered as the constraints which is a basis to judge the existence of bistable characteristics. The maximum relative error between finite element analysis results and optimal designs of surrogate models is 2.29%, which also reflects the accuracy of surrogate models. Two optimal designs of bistable laminates that verifies by the experimental investigations have been obtained. The maximum relative error of trigger force between the experimental and finite element analysis results is 14.28%, and the maximum relative error of the sum curvature of different stable states between the experimental and finite element analysis results is 9.22%. The proposed optimization technique can be applied to optimize composite structures in consideration of multi-objective. [ABSTRACT FROM AUTHOR]

Flexible photoresponsive transparent wood (FPTW) has potential applications in electronic equipment, sensors, and other fields. In this study, flexible and photoresponsive transparent wood was synthesized through the impregnation process, utilizing epoxy resin and a spiropyran solution. This process endowed the wood with intelligent response and flexible capabilities. Scanning electron microscopy (SEM) revealed the impregnation of the flexible polymer into the porous structure of natural wood. Further validation was conducted to affirm the sample responds to ultraviolet light, employing analyses of infrared spectroscopy, UV–visible spectroscopy, and X-ray photoelectron spectroscopy (XPS). Through the measurement of chromaticity parameters, encompassing lightness (L*), redness (a*), yellowness (b*), and total color difference (ΔE*), before and after UV irradiation, it is indicated that the wooden samples manifest commendable photoresponsive properties. Testing the fluorescence properties of the samples, the spiropyran completed the opened-loop and closed-loop transitions under irradiation with UV and visible light. In addition, the FPTW has excellent mechanical properties, with a tensile strength of 0.98 GPa and an elastic modulus of 0.65 GPa. [Display omitted] • Flexible photoresponsive transparent wood (FPTW) exhibits high transparency. • FPTW was fabricated by impregnating wood samples with spiropyran and epoxy resin. • FPTW demonstrated superior photoresponsiveness with ΔE* increasing from 0 to 23.90. • FPTW maintains excellent tensile performance even after 10 cycles of stretching. [ABSTRACT FROM AUTHOR]

• A magnetorheological elastomer actuated multi-stable gripper reinforced stiffness with twisted and coiled polymer. • The multi-stable gripper can conform objects with different sizes by means of its stable and adaptive characteristics. • The multi-stable gripper is composed of a multi-stable laminated composite shell as the grab unit for supporting, have multiple steady states. This study proposes a magnetorheological elastomer actuated multi-stable gripper reinforced stiffness with twisted and coiled polymer. The multi-stable gripper can conform objects with different sizes by means of its stable and adaptive characteristics. The multi-stable gripper is composed of a multi-stable laminated composite shell as the grab unit for supporting, a twisted and coiled polymer as the deformation element for variable stiffness and a magnetorheological elastomer as the smart material for actuation. The magnetorheological elastomer was activated by external magnetic field inducing the gripper change from the first stable state to the second or the third stable state to complete the gripping action. The driving force of the multi-stable laminated composite shell was discussed by the experimental and numerical methods, then the width of deformation and transition element was designed to reduce the driving force. Furthermore, the stiffness of the multi-stable gripper is analysed with respect to the compression, extraction, and gripping performance of the gripper through experiments, and then, the gripping performance was compared with current soft grippers. The experimental results show that the multi-stable gripper exhibits sufficient compliance and adaptability. That is, the multi-stable gripper has a faster response time and larger grasping weight compared with soft grippers. [ABSTRACT FROM AUTHOR]

• Thin-walled lenticular composite booms with different design parameters were prepared, and free-end loading experiments and coiling experiments are conducted on the established experimental platforms. • The finite element model of thin-walled lenticular composite booms are established and simulations are conducted to analyze the mechanical response during free-end loading and coiling process. • The influences of ply numbers, ply angles, fiber types and fiber contents on the performance of TLCBs were analyzed through experiments and finite element simulations. As a kind of lightweight composite structure, thin-walled lenticular booms made of fiber reinforced composite are widely used in the aerospace field because of its high stiffness in the unfolded state. In this paper, the load-bearing and coiling characteristics of the thin-walled lenticular composite booms were studied, and the effects of different design parameters and material properties were compared. Thin-walled lenticular composite booms with different ply numbers, ply angles, fiber types and fiber contents were prepared. Free-end loading experiments and coiling experiments were conducted to obtain the load-displacement curves, coiling torques and binding forces. The finite element model was established and the simulation results were compared with those of experiments. It is shown that increasing the ply number, increasing the fiber content and using fibers with lower elastic modulus can significantly enhance the load-bearing capacity of thin-walled lenticular composite booms, meanwhile reducing its coiling capacity. The booms with orthometric ply angle have greater load-bearing capacity, but the ply angle has less effect than the ply numbers, fiber types and fiber contents. The results provide feasibility for the design of thin-walled lenticular composite booms suitable for the aerospace field. [ABSTRACT FROM AUTHOR]

The morphing characteristics and damage analysis of variable stiffness bistable laminate fabricated by continuous fiber 3D printing technology are systematically studied. Conventionally, bistable structures used in morphing applications are achieved with straight fibers. With the application of fiber placement technology, it is now possible to prepare variable stiffness laminates with different directions and layup angles of fibers. Moreover, the structure will be damaged with the increase in deformation times. How to effectively suppress the failure of laminates is also a highlight for this composite structure. In this paper, three curvilinear fiber paths are designed and compared. And a semi-analytical model based on the Rayleigh-Ritz method is used to predict the curvature of stable configuration. In particular, continuous fiber thermosetting resin matrix composites 3D printing technology is proposed for preparing variable stiffness laminates, which has several advantages compared to other traditional preparation methods of variable stiffness laminates. The corresponding finite element model is also developed to investigate the bistable behavior and damage analysis. In addition, the influence of different angle parameters and fiber paths on the stable configuration and the snap-load are also discussed. Finally, the damage evolution and mechanical properties of straight-fiber laminates and variable stiffness laminates in tension and compression are carried out based on the Hashin failure criteria. [ABSTRACT FROM AUTHOR]

• The mechanical and buffering characteristics of laminate can be improved by adjusting the initial curing curvature. In this study, the influence of initial curing curvature on the negative stiffness and buffering characteristics of bistable laminates was analyzed. The geometric parameters and mechanical characteristics of bistable laminates may be affected by the initial curing curvature. Initially, a geometric nonlinear finite element model is developed, and its reliability is verified by comparing with experimental. The finite element model was used to investigate the influence of initial curing curvature on mechanical characteristics, including snap load, stiffness, and strain energy. On this basis, the influence of initial curing curvature on the buffering characteristics was studied by implicit dynamic analysis. The results of the study indicate that bistable laminates show pronounced negative stiffness characteristics during the snap process, which is not impacted by the stable state number. As a result of adjusting the initial curing curvature, the snap load and negative stiffness extremum can be designed, the strain energy difference can be adjusted, and the buffering range and efficiency of the laminate can be enhanced. [ABSTRACT FROM AUTHOR]

• This paper proposes a continuous fiber thermosetting resin matrix composite 3D printing technology, which aims to combine continuous fiber, thermosetting resin and 3D printing technology to realize the manufacture of multistable curvilinear-fiber laminates. • Continuous fiber 3D printing technology solves the limitation of interface separation or stress concentration caused by lap joints or mechanical connection in traditional multistable structures. • Continuous fiber 3D printing technology provide the possibility for free variation of fiber angle. Different from the traditional preparation process of curvilinear-fiber laminates, it shows unique advantages. A novel manufacturing method for curvilinear-fiber multistable laminates using continuous fiber 3D printing technology is proposed, and a numerical and experimental investigation on the morphing behavior is performed. Traditional multistable laminates are developed from multiple straight-fiber laminates jointed or bolted together, but the designability of straight-fiber laminates is limited. More importantly, the fibers at the lap joints or bolted connection are discontinuous or fractured, which cause interfacial separation or stress concentration. Different from the traditional preparation process, continuous fiber 3D printing technology ensures the continuity of adjacent deformable elements and integrity of the structure, thereby reducing the interfacial separation or stress concentration of the laminates caused by fiber discontinuity or fracture, and providing the possibility for free variation of fiber angle. Continuous fiber 3D printing technology further improves the design space for composites instead of traditional straight-fiber laminate. In this paper, two different curvilinear-fiber multistable laminates are designed and prepared, and a finite element model was developed to predict the possible cured configurations and analysis the snap behavior. The numerical and experimental results show good agreement in stable configurations and snap process. Subsequently, a parametric study is carried out to explore the effect of different angle parameters on the snap process and stable configurations. [ABSTRACT FROM AUTHOR]

A simple and efficient strategy of constructing ferrocene-based thioether ligands through metal-free reductive coupling of thiols with N -tosylhydrazones bearing a ferrocenyl group has been developed. This method features metal-free, good functional group tolerance, and readily available starting materials. Moreover, the compound 3k as a novel chemosensor has shown excellent recognition towards Hg 2+ ion via optical and electrochemical signals. Quantification of the absorption titration analysis shows that the detection limit was 9.56×10 −7 M for 3k -Hg 2+ . [ABSTRACT FROM AUTHOR]

Neutrophil extracellular traps (NETs) play critical roles in hepatic ischemic reperfusion injury (IRI) induced immune responses to inflammation. Diphenyleneiodonium (DPI) is an NADPH oxidative inhibitor that has been implicated in the regulation of NETs formation. However, the effects of NETs and their underlying mechanisms during DPI treatment of acute rejection (AR) after liver transplantation have not been elucidated. This study tested the hypothesis that blocking NETs formation by DPI treatment could be a potential therapeutic target against AR after liver transplantation. NETs were found to be excessively formed within the livers and serum of transplantation models, which could be an independent risk factor for AR. DPI was shown to alleviate hepatic injury and maintain liver functions by inhibiting NETs formation through the nicotinamide adenine dinucleotide phosphate (NADPH)/ROS/peptidylarginine deiminase 4 (PAD4) signaling pathway. NETs are highly involved in AR after liver transplantation. By inhibiting NETs formation, DPI suppresses activation of the NADPH/ROS/PAD4 signaling pathway which acts against AR after liver transplantation. Therefore, DPI is a potential candidate for the therapeutic management of AR after liver transplantation. Combination treatment containing both DPI and tacrolimus revealed a better antidamage efficacy than adjusting either treatment alone, suggesting that the joint therapy might be a promising solution in AR after liver transplantation. [ABSTRACT FROM AUTHOR]

In this study, a novel orthogonal bistable laminated composite shell driven by magnetorheological elastomer was developed. The magnetorheological elastomer served as the actuator of the stable transition between the two stable states of the bistable structure is rapid, reversible, non-contact and continuously controllable. The experimental results revealed that the trigger time of the stable transition can reach millisecond level. First, the magnetorheological elastomer and orthogonal bistable laminated composite shell were fabricated. Then, experiments and finite element simulations were conducted to measure the trigger force required to actuate the transition of the bistable structure. The experimentally measured trigger force agreed well with that estimated by the finite element simulation. The shape characteristics of the orthogonal bistable laminated composite shell were studied both in the presence and absence of the magnetorheological elastomer. The effect of the NdFeB content in the magnetorheological elastomer on the magnet field strength required to drive the transformation of the bistable structure was studied systematically, and a suitable magnetorheological elastomer was chosen to investigate the effects of the geometric dimensions of the magnetorheological elastomer actuator on the trigger magnetic field. The response time for the triggering of the transition of the bistable structure was measured, and the results indicated that the proposed magnetorheological elastomer actuation could be used to flexibly drive orthogonal bistable laminated composite shells. [ABSTRACT FROM AUTHOR]

A novel bistable hybrid composite laminate embedded with bimetallic strips was designed by combining the stable-state characteristics of the bistable laminate with the temperature-sensing characteristics of the bimetallic strip described in this paper. A contactless method that deforms the bimetallic strip through the temperature field, driving the bistable laminate, is proposed. Firstly, an analytical method based on Dano's theory was developed to determine the principal curvature of the laminates, and qualitative and quantitative comparisons between theoretical, experimental, and numerical results were conducted and showed good agreement. Then, the influence of bimetallic strip characteristics such as the thickness, width, and material properties, along with the aspect ratio of the laminates, on the principal curvature were examined. In addition, the reciprocating drive of the laminates was realized by changing the temperature generated by a thermal field, and the effect of the bimetallic strip arrangement was also studied. Compared with the conventional square bistable cross-ply laminates, it was found that the new laminates have different curvatures in two stable states. In particular, they can be easily driven by changing the ambient temperature (contactless drive), without requiring complicated external driving devices. This study provides theoretical support and a new driving method for the design of adaptive and deployable structures. A novel bistable hybrid composite laminate embedded with bimetallic strips was designed in this paper, and the temperature field was applied as a contactless driving method. Firstly, an analytical method based on Dano's theory was developed to determine the principal curvature of the laminates, and the qualitative and quantitative comparisons between theoretical, experimental and numerical results were conducted and showed a good agreement. Then, the influence of characteristics, such as the thickness, width and material properties of bimetallic strips, and the aspect ratio of the laminates on the principal curvature were examined. Besides, the reciprocating drive of laminates is realized by changing the temperature caused by a thermal field, and the effect of arrangement of bimetallic strips was also discussed. Comparing with the conventional square bistable cross-ply laminates, it is found that the new laminates have different curvatures in two stable states. Especially, it can be easily driven by applying a temperature field, without needing external complicated driving devices. It will provide theoretical support and a new driving method for the design of adaptive structures and deployable structures. [Display omitted] [ABSTRACT FROM AUTHOR]

• A cross-shaped unsymmetric laminates has three stable configurations. • The width will change the concave-convex boundary of the laminates. • The sidelength and width determine whether the laminate has multistability. This paper presents cross-shaped unsymmetric fibre-reinforced cross-ply laminates with concave–convex boundaries, which have three stable configurations. The third stable equilibrium configuration is a transition state which occurs in the snap process from the first to second equilibrium configurations. The snap processes, including the first–third–second and second–third–first, between the different stable equilibrium configurations of tristable cross-shaped unsymmetric laminates were investigated by experimental and numerical methods, and the parameters that characterise the tristable performance of the laminates, including the principal curvature, snap load, and displacement, were measured. The principal curvatures in different stable configurations were determined with analytical, experimental, and numerical methods, and the load–displacement curves and buckling phenomena in the snapping process were successfully recorded. Moreover, the influences of the reinforcement material, thickness of the single layer, and geometric parameters on the tristable performance of the cross-shaped unsymmetric fibre-reinforced cross-ply laminates were discussed. According to the results, the analytical, experimental, and numerical results agree well. [ABSTRACT FROM AUTHOR]

Soft robotics is an emerging research field that uses deformable materials or structures to fabricate compliant and adaptable systems through simple integrated mechanisms, thereby, enabling biomimetic behaviour. The Venus flytrap has the characteristics of excellent responsiveness and deformability, making it a promising inspirational model for the development of soft robotics. This paper presents a novel robotic gripper that mimics the trapping motion of the Venus flytrap. This gripper was implemented by exploiting a combination of bistable anti-symmetric shells and magnetic actuation. Two cylindrical shells constructed from carbon-fibre-reinforced polymer act as compliant fingers that can transform between two stable configurations based on external actuation. An applied clamped boundary condition reduces the actuation force required to trigger the morphing process. A novel non-contact magnetic actuation method with excellent responsiveness is proposed to actuate the compliant finger. The robotic gripper is designed to be lightweight and compact with high gripping force. Experiments and simulations were performed to analyse the gripping motion and measure the actuation force. The width of the clamped edge is the main factor influencing gripper performance as it relates to actuation force. The results of our analysis demonstrate that the proposed flytrap-inspired design with a bistable structure can be used to implement a novel robotic gripper controlled by a magnetic field. [ABSTRACT FROM AUTHOR]