Search

Background and Purpose: Melanogenesis is essential for pigmentation and deregulated melanogenesis causes pigmentary diseases. Psoralen and ultraviolet A (PUVA) therapy strongly stimulates pigmentation, but the underlying molecular mechanisms are elusive. Experimental Approach Melanin content of cultured human melanocytes was spectrophotometrically measured. Patch‐clamp recordings were made in human melanocytes or HEK 293 cells transiently expressing wild type or mutant human TRPV1 and TRPA1 channels. Endogenous expression of TRPV1 and TRPA1 in melanocytes was analysed by western blotting and was knocked down with siRNA. In vivo pigmentary responses were measured by a colorimeter in mouse ear skin. The expression of TRPV1 and TRPA1 in human pigmented lesions was examined by immunohistochemical staining. Key Results: PUVA strongly stimulated melanogenesis and PUVA‐induced TRPV1 and TRPA1 channel activation in melanocytes and the resulting Ca2+ influx were required for the stimulated melanogenesis both in vitro and in vivo. Agonists‐induced TRPV1 and TRPA1 activation alone did not stimulate melanogenesis, but it synergized UVA or intrinsic cAMP and NO signalling pathways to stimulate UV‐dependent or UV‐independent melanogenesis. Moreover, the expressions of TRPV1 and TRPA1 were increased in human melanocytic lesions and inhibition of both channels decreased melanin content in melanoma cells. Conclusion and Implications: TRPV1 and TRPA1 are key molecular sensors and enhancers of extrinsic and intrinsic melanogenic signals in both physiological and pathological conditions, and activation of both channels in melanocytes contributes to PUVA therapy‐induced pigmentation. Our work provides a common mechanism of melanogenic regulation and highlights TRPV1 and TRPA1 as potential therapeutic targets for pigmentary disorders. [ABSTRACT FROM AUTHOR]

The strip model, which is currently the most commonly used simplified analytical model for steel plate shear walls (SPSWs), neglects the compressive stiffness and resistance of the infill plate, thus underestimating the lateral stiffness and ultimate strength. Therefore, in this study, a more general simplified analytical model, the uniform strip model, is developed for SPSWs with different web plate thicknesses. The new model incorporates the compressive stiffness and resistance of the infill plate by adjusting the cross-sectional area and yield stress of the strips of the original strip model. The numerical simulations of experimental specimens demonstrate the validity of the new model. Parametric studies were performed to investigate the effects of the aspect ratio, plate thickness, and story number on the accuracy of the proposed model relative to a detailed shell element model. The results demonstrate that the uniform strip model agrees well with the shell element model. In comparison, the original strip model is most suitable only for what is classified as thin SPSWs, and the proposed model is a feasible tool for modeling buckling-restrained SPSWs. [ABSTRACT FROM AUTHOR]

In order to solve the problems of poor electrical conductivity and low material utilisation of MnO2 materials in water-based zinc-ion batteries (ZIBs), this paper took agricultural waste coconut shells as raw materials, introduces low-cost, abundant, and green renewable biomass resources into electrode materials, and obtained coconut shell carbon with excellent conductivity through high-temperature carbonization. MnO2 nanopar-ticles were grown on the surface of coconut shell carbon by hydrothermal method to obtain coconut shell carbon@MnO2 composite nanomaterials. By using scanning electron microscopy (SEM), X-ray diffraction (XRD), electrochemical techniques and other characterization testing methods, the morphology, structure, and electrochemical performance of the composite material were analyzed. The results showed that the specific capacity of coconut shell carbon@MnO2 was still as high as 344.6 mA h/g after 300 cycles at a current density of 100 mA/g, and its performance was much higher than that of commercial MnO2 materials (64.3 mA h/g). The excellent electrical conductivity of coco carbon@MnO2, the nanosized structural design improved the material utilisation, reduced the ionic diffusion path, brought faster ionic diffusion rate and improved the multiplicity performance of the material, which had a good application prospect. [ABSTRACT FROM AUTHOR]

Red phosphorus is a promising anode material for sodium-ion batteries due to its low cost and superior theoretical capacity of 2596 mAh g−1. However, intrinsically inferior conductivity and huge volume changes during sodiation/desodiation processes hinder its practical application. Herein, we report an integrated red phosphorus/N-doped biomass carbon composite via filling red phosphorus nano-particles into the nano-pores of N-doped carbon derived from a renewable coconut shell biomass. In the rational structural design, N-doped biomass carbon serves as hard template for embedding red phosphorus nano-particles, buffers the volume expansion of red phosphorus during sodiation processes, and enhances the conductivity of composite. The composite delivers a high reversible capacity of 2481 mAh g−1 at 50 mA g−1 with a higher 89% initial coulombic efficiency. When the current density increases by 100 times to 5000 mA g−1, the capacity can remain 855 mAh g−1. Moreover, the composite maintains a reversible capacity of 1857 mAh g−1 at 500 mA g−1 after 100 cycles, and 845 mAh g−1 at 2000 mA g−1 after 500 cycles. This work introduces abundant biomass into application of high performance electrode materials for sodium-ion batteries. • Low-cost, renewable and abundant coconut shell biomass as carbon source. • The rational design gives a full play to the synergistic effect of rP and N-BC. • rP provides high capacity. • N-BC buffers the volume changes of rP and enhance the conductivity. • The rP@N-BC composite exhibits superior sodium storage performance. [ABSTRACT FROM AUTHOR]

Borneol has been used successfully for the treatment of itchy skin in traditional Chinese medicine. However, the antipruritic effect of borneol has rarely been studied, and the mechanism is unclear. Here, we showed that topical application of borneol on skin substantially suppressed pruritogen chloroquine- and compound 48/80-induced itching in mice. The potential targets of borneol, including transient receptor potential cation channel subfamily V member 3 (TRPV3), transient receptor potential cation channel subfamily A member 1 (TRPA1), transient receptor potential cation channel subfamily M member 8 (TRPM8), and gamma-aminobutyric acid type A (GABA A) receptor were pharmacologically inhibited or genetically knocked out one by one in mouse. Itching behavior studies demonstrated that the antipruritic effect of borneol is largely independent of TRPV3 and GABA A receptor, and TRPA1 and TRPM8 channels are responsible for a major portion of the effect of borneol on chloroquine-induced nonhistaminergic itching. Borneol activates TRPM8 and inhibits TRPA1 in sensory neurons of mice. Topical co-application of TRPA1 antagonist and TRPM8 agonist mimicked the effect of borneol on chloroquine-induced itching. Intrathecal injection of a group II metabotropic glutamate receptor antagonist partially attenuated the effect of borneol and completely abolished the effect of TRPM8 agonist on chloroquine-induced itching, suggesting that a spinal glutamatergic mechanism is involved. In contrast, the effect of borneol on compound 48/80-induced histaminergic itching occurs through TRPA1-and TRPM8-independent mechanisms. Our work demonstrates that borneol is an effective topical itch reliever, and TRPA1 inhibition and TRPM8 activation in peripheral nerve terminals account for its antipruritic effect. [ABSTRACT FROM AUTHOR]

The stability of prismatic columns subjected to internal axial loads is a common issue during engineering analysis and design. Because of the big difference between the effects of internal loads and end loads, the traditional effective length method is not applicable. Current codes do not provide design method for this issue and engineers require the ability to analysis and design this kind of columns efficiently. Using the concept of negative stiffness, a relationship between end loads and internal axial loads applied on sway-permitted prismatic columns is established so that the internal loads can be considered equivalent to end loads and the critical value can be obtained easily by Euler formula. A practical method to determine the second-order effect is also developed. Eigenvalue buckling and elastic nonlinear analyses are performed to examine the proposed method and the comparison results indicate it has high accuracy. [ABSTRACT FROM AUTHOR]

Abstract: Stochastic noise in a fiber optic gyro (FOG) is mainly caused by white noise and 1/fγ fractal noise. The latter noise is characterized by long-term correlation, self-similarity and spectral density with 1/fγ power law. The application of the empirical mode decomposition (EMD) method and the lifting wavelet transform (LWT) as a novel EMD–LWT technique has been proposed and implemented in denoising the stochastic noise generated for a FOG. The EMD method is a novel nonlinear and non-stationary signal processing method and the LWT is a lifting scheme of wavelet transform. Experimental results of the FOG data have validated the feasibility of the proposed method, which is more effective than the denoising methods that use either LWT or the EMD method. [Copyright &y& Elsevier]

Abstract: A major challenge for most tracking algorithms is how to address the changes of object appearance during tracking, incurred by large illumination, scale, pose variations and occlusions. Without any adaptability to these variations, the tracker may fail. In contrast, if adapts too fast, the appearance model is likely to absorb some improper part of the background or occluding objects. In this paper, we explore a tracking algorithm based on the robust appearance model which can account for slow or rapid changes of object appearance. Specifically, each pixel in appearance model is represented using mixture Gaussian models whose parameters are on-line learned by sequential kernel density approximation. The appearance model is then embedded into particle filter framework. In addition, an occlusion handling scheme is invoked to explicitly indicate outlier pixels and deal with occlusion events, thus avoiding the appearance model to be contaminated by undesirable outlier ‘thing’. Extensive experiments demonstrate that our appearance-based tracking algorithm can successfully track the object in the presence of dramatic appearance changes, cluttered background and even severe occlusions. [Copyright &y& Elsevier]

In this paper, support vector machine (SVM) is described and applied in the temperature drift modeling and compensation to reduce the influence of temperature variation on the output of dynamically tuned gyroscope (DTG) and to enhance its precision. To improve the modeling capability, empirical mode decomposition (EMD) is introduced into the SVM model to eliminate any impactive noises. The real temperature drift data set from the long-term measurement system of a certain DTG is employed to validate the effectiveness of the proposed combination model. The modeling and compensation results indicate that the proposed EMD-SVM model outperforms the neural network (NN) and single SVM models, and is feasible and effective in temperature drift modeling and compensation of the DTG. [Copyright &y& Elsevier]

Abstract: In the framework of evidence theory, data fusion is to build a single belief function by combining several belief functions derived from distinct information sources. Dempster’s rule of combination, a classical combination rule with several interesting mathematical properties, is widely employed. However, as an inherent problem, Dempster’s rule of combination is incapable of managing the existing conflicts from various information sources at the step of normalization. The conflict management becomes an important problem in the operation of combination, especially in the condition of highly conflicting, which leads to produce the illogical result of combination. In this paper, we introduce the idea of grey relational analysis (GRA), and propose a new conflict reassignment approach of belief functions, as a preprocessing method, to automatically identify and reassign the conflicts on belief functions before combination. Three numerical examples are employed and implemented. Through analysis and comparison of the combined results, of the existing alternatives, the proposed approach not only can flexibly solve the problem of conflict management with better convergence performance, but also can automatically evaluate the reliability of the information sources and distinguish the unreliable information. [Copyright &y& Elsevier]

The effective length factors of stepped columns, as provided by current design codes, neglect the interaction effect among the columns. Considerable inaccuracies could be introduced because this effect can be significant for stepped columns. This study aimed to reveal the mechanism of the interaction effect among sway-permitted stepped columns and develop a practical approach to consider this effect. Stiffness matrices were first obtained for three- and two-segment stepped columns using the slope-deflection method, and equations for lateral stiffness were developed. Next, we analysed the effect of compressive loads on the lateral stiffness of the columns. The results showed that the relationship between the normalised column stiffness and axial load could approximately be described as a broken line and the second-order effect produced by the applied axial compressive loads could be regarded as a 'negative stiffness'. Based on these findings, equations were developed to calculate the effective length factors of three- and two-segment stepped columns considering the interaction effects among them. Examples derived from practical projects demonstrated the validity of the proposed approach. • Evaluated effective length factor for framed-stepped column. • Interaction effect among columns was considered. • Proposed approach exhibits high accuracy and ease of implementation. • The proposed approach and eigenvalue analysis differed by less than 0.8%. [ABSTRACT FROM AUTHOR]

The effective length factors of stepped columns, as provided by the current design codes, are not suitable for certain situations, such as multi-bay frames and pitched-roof portal frames, because the interaction effect among the columns and the influence of the roof inclination angle are not considered. This paper proposes a simple but accurate hand calculation method to evaluate the effective length factors and second-order effects on framed stepped columns. In this approach, the expression of the negative lateral stiffness for stepped columns is first determined and then used to determine the effective length factors considering the interaction effects among columns. This is followed by a theoretical analysis to evaluate second-order effects, and expressions for calculating the deflection and moment amplification factors are developed. A practical method to account for the influence of the roof inclination angle for frames with stepped columns is also presented. The results of the performed eigenvalue and nonlinear static analyses demonstrate the validity of the proposed method. Based on the presented analysis, recommendations are made for the improvement of current design codes. Finally, the values of the key factors, α s 0 and α sN , for some common cases are determined. The findings will assist in the development of reliable and cost-efficient designs of stepped columns in mill buildings. • Evaluated effective length factor and second-order effect for framed-stepped columns. • Interaction effect among columns was considered. • Proposed approach is simple and applicable to wide range of frame types. • Proposed approach exhibits high accuracy and ease of implementation. [ABSTRACT FROM AUTHOR]

This study proposes a coupled system of steel plate shear wall with slits (SPSWS), called C-SPSWS. The mechanical behavior of the C-SPSWS system was investigated, and the expressions for ultimate strength and degree of coupling (DC) were derived according to the desired plastic mechanism. Two one-third scale, four-story specimens, including coupled and uncoupled SPSWS, were tested to verify the seismic performance of the system. As the traditional SPSWS configuration, the C-SPSWS specimen exhibited robust cyclic performance and proved to be an efficient lateral load-resisting system. The coupling action of the coupling beam significantly improved the initial stiffness, strength, and energy dissipation capacity of the system. Furthermore, the coupling action decreased the axial force of the frame columns, particularly for interior frame columns. The deformation mode of the C-SPSWS specimen changed from flexural to shear because of the coupling action. The proposed ultimate strength formula can conservatively predict the maximum lateral force of the system. • A coupled system of steel plate shear wall with slits was proposed. • The expressions for the C-SPSWS system strength and the DC were derived based on the desirable plastic mechanism. • The failure mode and yielding sequence of the coupled system were obtained through cyclic quasi-static tests with two large-scale, weak-axis connected coupled and uncoupled specimens. • The coupling action can improve the initial stiffness, lateral strength, and energy dissipation capacity of the coupled system while decreasing the axial demands of the frame columns. • The deformation mode of the coupled specimen changed from flexural to shear due to the coupling action. [ABSTRACT FROM AUTHOR]

Steel plate shear wall is usually in the form of a tube as the lateral force-resisting component in high-rise buildings. In addition to the connection between the column flange and beam section, the connection between the column web and beam section (i.e. the weak-axis connection) is also required. Therefore, the hysteretic behavior of uncoupled and coupled steel plate shear walls with this connection form was studied. Cyclic loading tests were carried out on two 1/3 scaled four-story specimens consisting of the uncoupled and coupled steel plate shear wall specimens (S4RN and C4RN). The test results show that the weak-axis connected form makes the column avoid premature out-of-plane deformation; the coupled specimen has better performance than the uncoupled specimen with a higher ductility of 4.31, and both specimens tend to a similar angle of 45° in the direction of the tension band; the coupling beam can effectively enhance the bearing capacity, improve the pinch of the hysteresis loop, and its rotation exhibits a similar tendency to that inter-story rotation while hitting the max of 0.07rad. A numerical method to simulate the behavior of S4RN and C4RN, and the submodel solution strategy to investigate the improvement of infill plates, are proposed and implemented using the ABAQUS. The specimens' shear distribution and partially slotted infill plate configuration were examined after the numerical modeling method was validated against the test results. The numerical results show that approximately 60% of the total lateral force can be shared by the infill plates, and the coupling beams can further reduce the lateral force resisted by the infill plates. The coupling beams can effectively reduce the overturning moment of each wall pier and adjust the axial pressure between the inner and outer column. The partially slotted CSPSW exhibits a plump spindle-shaped hysteretic curve with a great ductility of 5.88, so the measurement for replacing ordinary infill plates with partially slotted infill plates has a good application prospect. • We originally developed a large-scaled experimental program to investigate the cyclic characteristics of uncoupled and coupled steel plate shear wall. • We also originally proposed an improved infill plate configuration with partially slotted infill plates incorporated in the steel plate shear walls. • A new connection between column web and beam section (i.e. the weak-axis connection) was proportioned to transform internal force between columns and beams. • The strain state, axial pressure state, inclination of tension band and the overall rotation for coupling beams were also examined. • The submodel solution strategy to investigate the improvement of infill plates, are proposed and implemented using the ABAQUS. [ABSTRACT FROM AUTHOR]

In a coupled steel plate shear wall, the interaction between two steel plate shear wall piers enabled by the coupling beams improves the overturning capacity of the lateral force–resisting system. Furthermore, the boundary frames and coupling beams contribute significantly to the lateral strength of the system. This study presents an equation to quantify the relationship between the overstrength of the coupled steel plate shear wall and the percentage of the lateral seismic design force resisted by the web plates alone. This equation can be used in design to proportion the strength of web plates, the boundary frames, and the coupling beams. Two coupled steel plate shear wall archetype sets with different ranges of the degree of coupling (i.e., less than 0.4 and between 0.4 and 0.6) were designed considering the contribution to lateral strength from all components and their collapse performance was evaluated. Pushover and incremental dynamic analyses were conducted. The material models for the web plates, boundary frames, and coupling beams included deterioration. The analyses indicated that the complete strength of the system (i.e., the strength of the web plates, boundary frame and coupling beams) may be considered when the degree of coupling is above 0.4. When it is lower, a minimum overstrength is necessary to ensure that the seismic performance factors provide acceptable collapse performance. [ABSTRACT FROM AUTHOR]

Abstract: Empirical mode decomposition (EMD), a new self-adaptive signal processing method, has been recently developed for nonlinear and non-stationary time series analysis. In this paper, EMD method is described and employed for signal denoising. Aiming at the problems of intrinsic mode function (IMF) criterion in the EMD method, neural network (NN) prediction model and wavelet packet transform (WPT) technology are simultaneously introduced into the EMD method to improve the border effect and to enhance the ability of signal denoising, and thus a type of hybrid EMD-based model is proposed and applied in drift denoising for a dynamically tuned gyroscope (DTG). Experimental results on real drift data from the long-term measurement system of a certain DTG indicate that the proposed hybrid model is feasible and more effective in drift denoising compared with the wavelet and single EMD denoising methods. [Copyright &y& Elsevier]

Environmentally-friendly carbon-based materials possess the potential applications as general anode for alkali-ion batteries. However, the existing carbon-based materials cannot satisfy the increasing demand for high energy density and need further active exploration. Herein, nitrogen/oxygen co-doped graphene-like carbon nanocages (NOGCN) is synthesized from biomass cytidine on hydro-soluble sodium chloride nanocrystals by a one-step method as a general lithium and potassium-ion batteries anode. All reactants are completely renewable and readily available. The nitrogen/oxygen-doping, large interlayer spacing and robust self-supporting nanocage architecture greatly favour electrolyte penetration and improve the kinetics for ion and electron transport, resulting in extraordinary electrochemical performance. The synthesized NOGCN electrodes exhibit a high lithiation storage capacity of 620 mA h g−1 over 500 cycles at 500 mA g−1, with continuously magnifying capacity. Moreover, the impressive reversible potassiation capacity (355 mA h g−1 at 200 mA g−1) and rate capability (114 mA h g−1 at 1000 mA g−1) were achieved despite the large-sized potassium ions. Kinetic analysis and density functional theory calculations elaborately illustrate the Li/K-absorption properties of the N/O-doped graphene-like structure, further demonstrating the chemical affinity and superiority in Li/K storage. This study provides a facile and completely renewable method to prepare promising general anode material for alkali-ion batteries. Image 1 [ABSTRACT FROM AUTHOR]

Adenanthin, a natural ent-kaurane diterpenoid extracted from the herb Isodon adenantha, has been reported to increase intracellular reactive oxygen species in leukemic and hepatocellular carcinoma cells. However, the function and mechanism of the compound in adipogenesis and the development of obesity is still unknown. In this study, we demonstrated that adenanthin inhibited adipogenesis of 3T3-L1 and mouse embryonic fibroblasts, and the underlying mechanism included two processes: a delayed mitotic clonal expansion via G0/G1 cell cycle arrest by inhibiting the RB-E2F1 signaling pathway and a reduced C/EBPβ signaling by inhibiting the expression and activity of C/EBPβ during mitotic clonal expansion. Furthermore, adenanthin significantly reduced the growing body weight and adipose tissue mass during high-fat diet-inducing obesity of mice, indicating the beneficial effects of adenanthin as a potential agent for prevention of obesity. [ABSTRACT FROM AUTHOR]

Pure ZnO, Ag-doped ZnO, Ce-doped ZnO, and co-doped ZnO (Ag–Ce/ZnO) nano-photocatalysts were synthesized by the hydrothermal method. Compared with pure ZnO, Ag-doped ZnO, Ce-doped ZnO, and Ag–Ce/ZnO exhibited excellent photocatalytic performance due to their superior optical and photoelectrochemical properties. Photodegradation experiment results revealed that the Ag–Ce/ZnO photocatalysts could degrade 97% of RhB dye within 30 min. Further, it was proved that the superoxide radicals played an active role in the photodegradation reaction. A possible mechanism of Ag–Ce/ZnO degradation was proposed. • Ag and Ce co-doped ZnO nano-photocatalysts are prepared by a facile hydrothermal method. • The photocatalytic performance of Ag and Ce co-doped ZnO is 15.1 times higher than that of pure ZnO. • The photocatalytic mechanism of Ag and Ce co-doped ZnO photocatalysts is proposed. [ABSTRACT FROM AUTHOR]

Abstract: Binder plays a key role in maintaining the mechanical integrity of electrodes in lithium‐ion batteries. However, the existing binders typically exhibit poor stretchability or low conductivity at large strains, which are not suitable for high‐capacity silicon (Si)‐based anodes undergoing severe volume changes during cycling. Herein, a novel stretchable conductive glue (CG) polymer that possesses inherent high conductivity, excellent stretchablity, and ductility is designed for high‐performance Si anodes. The CG can be stretched up to 400% in volume without conductivity loss and mechanical fracture and thus can accommodate the large volume change of Si nanoparticles to maintain the electrode integrity and stabilize solid electrolyte interface growth during cycling while retaining the high conductivity, even with a high Si mass loading of 90%. The Si‐CG anode has a large reversible capacity of 1500 mA h g−1 for over 700 cycles at 840 mA g−1 with a large initial Coulombic efficiency of 80% and high rate capability of 737 mA h g−1 at 8400 mA g−1. Moreover, the Si‐CG anode demonstrates the highest achieved areal capacity of 5.13 mA h cm−2 at a high mass loading of 2 mg cm−2. The highly stretchable CG provides a new perspective for designing next‐generation high‐capacity and high‐power batteries. [ABSTRACT FROM AUTHOR]