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[Display omitted] • A negative spiropyran with a visible light response is successfully synthesized. • Merocyanine diol is first used as an intelligent electrolyte. • A visible light sensor with a simple structure is successfully prepared. • A core-sheath flexible conductive fiber with visible light sensing is fabricated. Flexible conductive fibers have attracted significant attention in the wearable electronics field because of light weight, small size, and easy shape morphing. To date, there are few reports on multifunctional flexible conductive fibers. Finding a facile and effective solution for large-scale production of flexible conductive fibers is still a challenge. In this work, a flexible core-sheath fiber with excellent electrical conductivity (24.71 Ω·m) and visible light sensing is fabricated, which contains a merocyanine diol (MC(OH) 2)/CrCl 3 ·6H 2 O/ethanol aqueous solution core layer and a silicon rubber outer layer. The synthesized MC(OH) 2 is an intelligent molecular switch with a visible light response that can reversibly convert from open-form MC(OH) 2 to closed-form spiropyran diol (SP(OH) 2) after short visible light irradiation. In the reverse process, the transition from SP(OH) 2 to MC(OH) 2 can occur gradually in the dark. This can be used to sense visible light in addition to electrical conductivity. The reversible change in the electrical resistance of the MC(OH) 2 /CrCl 3 ·6H 2 O/ethanol aqueous solution reaches 15.59%. This fiber shows excellent electrical conductivity, good flexibility, a sensitive visible light response, good photochromism, a simple structure, low cost, easy preparation, and suitability for industrial large-scale production, offering promise for applications in the fields of flexible and wearable electronics. [ABSTRACT FROM AUTHOR]

A Nile red (NR) dye cathode with an asymmetric redox structure of para C＝N and C＝O bonds was developed for use in an efficient lithium organic battery with a good capacity of 125 mA h g−1 and two visible discharge/charge voltage plateaus (≈2.0 V and ≈1.7 V). The NR cathode demonstrated the advantages of employing cost-effective dyes to achieve multigradient voltage platform regulation. [ABSTRACT FROM AUTHOR]

Visible light is an important energy source for all living organisms on Earth. Given the importance of visible light, visible light sensors have attracted widespread interest from scientists. With the rapid development of wearable devices, the sensors used in them need to be flexible, stretchable, and lightweight. Herein, an intelligent electrolyte based on spiropyran (SP) that responds to visible light is developed. The reversible change rate in the electrical resistance of an SP/FeCl3·6H2O methyl cyanide (MeCN) aqueous solution under visible light irradiation is as high as 19.26%. Additionally, flexible and conductive fibrous visible light sensors with a core‐sheath structure are prepared using an SP/FeCl3·6H2O MeCN aqueous solution and silicon rubber hollow fibers as the core and outer layers, respectively. These fibrous visible light sensors are then woven into fabrics with multiple functions, such as sensing and locating visible light, reversible photochromism, and thermal management. The fibrous visible light sensors and fabrics prepared in this study have broad development prospects and application potential in the fields of fashion, smart textiles, flexible conductive fibers, flexible fibrous sensors, electronic skins, and wearable devices. [ABSTRACT FROM AUTHOR]

Polyimide (PI) refers to a type of high-performance polymer containing imide rings in the main chain, which has been widely used in fields of aerospace, microelectronic and photonic devices, gas separation technology, and so on. However, traditional aromatic PIs are, in general, the inefficient fluorescence or even no fluorescence, due to the strong inter- and intramolecular charge transfer (CT) interactions causing unavoidable fluorescence quenching, which greatly restricts their applications as light-emitting functional layers in the fabrication of organic light-emitting diode (OLED) devices. As such, the development of fluorescent PIs with high fluorescence quantum efficiency for their application fields in the OLED is an important research direction in the near future. In this review, we provide a comprehensive overview of fluorescent PIs as well as the methods to improve the fluorescence quantum efficiency of PIs. It is anticipated that this review will serve as a valuable reference and offer guidance for the design and development of fluorescent PIs with high fluorescence quantum efficiency, ultimately fostering further progress in OLED research. [ABSTRACT FROM AUTHOR]

Perylene dianhydride (PDA), a low-cost, readily available, and chemically stable organic cathode material, has received extensive attention in recent years. However, its large π planar structure often results in poor or difficult-to-control micro-nanostructures during conventional electrode processing methods, such as dry mixing. This leads to limited cycling life and rate performance. Here, we present a simple electrospinning strategy for controlling the micro-nanostructures of electrodes based on PDA, carbon black Super P (SP), and polyvinylidene fluoride (PVDF) composites. The spinnable PVDF polymer not only provides the micro-nanofibrous structure but also realizes the function of the binder in the electrodes, offering the hierarchical micro-nanostructures of the electrospun PDA (PDA-es) electrodes. The unique structure enables PDA-es electrodes to possess rapid charge transport properties and ultrafast reaction kinetics. Specifically, the PDA electrode based on high molecular weight electrospun PVDF (PDA-es-H) demonstrates a high initial specific capacity (126.2 mA h g−1), robust cycling stability (∼95% and ∼60% capacity retention after 100 cycles at 50 mA h g−1 and 1000 cycles at 100 mA h g−1, respectively), and excellent rate performance. This study provides a straightforward and efficient strategy for realizing the micro-nanostructures of organic electrodes for high-performance lithium-organic batteries. [ABSTRACT FROM AUTHOR]

An in situ gel separator based on an electrospun three-layer nanofibrous membrane (PSE11-Gel) is developed for high-performance lithium-organic batteries (LOBs). The highly efficient shuttle effect inhibition of organic cathode molecules or lithiated intermediates has been demonstrated for PSE11-Gel to realize high-capacity stable LOBs. [ABSTRACT FROM AUTHOR]

Effectively guiding and accurately controlling cell adhesion and growth on the surfaces of specific morphological materials are key issues and hot research topics for optimizing biomaterials. Herein, novel polymorphic alginate microfibers formed through microfluidic spinning technology in a single microchip are presented. Through programming the flow and reaction kinetics in microchannels, other than self-modified micromorphic channel geometry, polymorphic microfibers with precisely tuned curvature-adjustable morphology can be obtained. Finite element (FE) simulations of the flow field (unidirectional fluid–solid coupling) proved the efficacy of the proposed control strategy. Moreover, the specific disordered–ordered cell arrangements showed a linear relationship between bioinspired alginate microfibers with different curvatures and the orientation angle of L929 cells, and diversified growth morphologies, including oblate ellipse, star, tree and strip shapes, occurred on the customizable interface curvature of the calcium alginate microfibers, providing a paradigm for using specific structured natural biomedical materials for cell regulation. This work represents a new design concept for manufacturing polymorphic fibrous biomedical materials through a unique marriage of the fields of green chemistry, hydromechanics, and biomaterials, which should be very useful for guiding the controllable construction of alginate materials for use in structural materials for biomedical and engineering purposes. [ABSTRACT FROM AUTHOR]

We propose a novel subsurface pipeline mapping and 3D reconstruction method by fusing ground-penetrating radar (GPR) scans and camera images. To facilitate the simultaneous detection of multiple pipelines, we model the GPR sensing process and prove hyperbola response for general scanning with nonperpendicular angles. Furthermore, we fuse visual simultaneous localization and mapping outputs, encoder readings with GPR scans to classify hyperbolas into different pipeline groups. We extensively apply the J-linkage method and maximum likelihood estimation with error analysis to improve algorithm robustness and accuracy. As a result, we optimally estimate the radii and locations of all pipelines. We have implemented our method and tested it in physical experiments with representative pipeline configurations. Two different kinds of 3-m-long pipes are used, with radii being 4.62 and 3.02 cm, respectively. The results show that our method successfully reconstructs all subsurface pipes. Moreover, the average estimation errors for two orientation angles of pipelines are 1.73° and 0.73°, respectively. The average localization error is 4.47 cm. Note to Practitioners—Automatic and accurate underground pipeline mapping technology is very important in civil construction projects. Lack of 3D utility pipeline maps may lead to accidental damage in civil construction and maintenance. Although ground-penetrating radar (GPR-based pipeline mapping methods have been studied for several years, these methods require the perpendicular scanning with respect to the pipe, which is impossible to guarantee in practice since the orientations of pipelines are unknown. Furthermore, these traditional methods can only estimate one pipeline at a time in a survey area and require prior knowledge of pipe diameter. We propose a robotic subsurface pipeline mapping method with a GPR and a camera to handle difficult factors such as multiple pipes, unknown pipeline orientation, and unknown pipeline diameters. Hence, we can perform GPR scanning along any generic linear trajectories. Our method has been tested in physical experiments with representative pipeline configurations. The results are sufficiently accurate, and it proves that our method can be an effective technology to reconstruct the underground pipelines. [ABSTRACT FROM AUTHOR]

[Display omitted] • PPVN-EFS can realize K+ detection in sweat with large-scale for garment integration. • The warp and weft of PPVN-EFS can achieve absorbing sweat in skin sensing area by interaction. • PPVN-EFS can achieve rapid respond (≤2.1 s) and long-term stable sensing (≥6000 s). Currently, most electrochemical sensors use thin films, single fiber or yarn as sensing unit. However, the weaving process remains challenging along with properties such as a large sensing area, rapid response and long-term stable monitoring. Herein, an electrochemical fabric sensor was developed based on a skin-core structured sensing yarn for in-situ monitoring of potassium ion (K+) concentrations in human sweat and this was achieved through a simple but novel electro-assisted core spinning technique (EACST). The nanofibers in the skin layer of the induction yarn showed excellent hydrophilicity and high specific surface area (8.85 m2/g) as well as significant differences in hydrophilicity and hydrophobicity of the warp and weft yarns of the fabric. As such, they could achieve absorption of sweat limit domain in the skin sensing area, so that the sensor can respond quickly within a short time (2.1 s) and achieve long-term stable sensing (above 6000 s). In addition, the sensor exhibited excellent selectivity, potential reproducibility as well as low noise and signal drift (3.6 × 10−2 mV/s). The large-area (55 cm × 35 cm) of the electrochemical fabric sensor could also be sewn into clothing for integration onto the human body where it could effectively collect sweat for real-time in-situ monitoring of K+ signals in human sweat. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) constitutes a major global health threat due to the high incidence and mortality. Sorafenib is known as the first-line medication for advanced HCC; however, it only extends the limited benefit for HCC patients as the development of acquired resistance. Withaferin A exerts broad pharmaceutical applications in several cancers. However, its effects on HCC cell metastatic potential and sorafenib resistance remain elusive. Here, we corroborated that Withaferin A greatly restrained cell viability, invasion, vasculogenic mimicry (VM) formation, and VE-cadherin levels in HepG2 and SNU449 cells. Moreover, Withaferin A sensitized sorafenib (SR)-resistant HCC cells to sorafenib. In striking contrast to the parental cells, lower ferroptosis was observed in SR-resistant cells as the lower ROS, MDA, and higher intracellular GSH levels in SR-resistant cells. Of interest, Withaferin A enhanced ferroptosis in SR-resistant cells, which was reversed by ferroptosis antagonist liproxstation-1. Notably, Withaferin A elevated Keap1 expression to mitigate Nrf2 signaling activation-mediated epithelial to mesenchymal transition (EMT) and ferroptosis-related protein xCT expression. Importantly, blockage of the Keap1/Nrf2 signaling overturned Withaferin A-evoked ferroptosis and facilitated sorafenib resistance. In addition, knockdown of Keap1 antagonized the inhibitory efficacy of Withaferin A on HCC cell viability, invasion, and VM formation. Consequently, Withaferin A may attenuate the metastatic potential and sorafenib resistance by regulating Keap1/Nrf2-associated EMT and ferroptosis. Thus, Withaferin A may serve as a promising agent for HCC therapy, especially for advanced HCC. [ABSTRACT FROM AUTHOR]

Radiation protective materials are widely applied to avoid occupational hazards from either particle emissions or high-energy electromagnetic waves. Herein, we present a boron imidazolate framework (BIF) as a novel neutron shielding additive with high neutron capture cross-section elements B/Li and H. The BIF1-based epoxy resin matrix (Ep-BIF1) possesses high thermal stability and excellent resistance capacity. The neutron radiation shielding property was characterized using an Am–Be source, in which the thermal neutron shielding efficiency of Ep-BIF1 is notably higher than that of Ep-B4C with equal boron concentration, showing potential applications as an advanced efficient neutron radiation shielding composite. [ABSTRACT FROM AUTHOR]

Recently, the siamese convolutional neural network plays an important role in the field of visual tracking, which can obtain high tracking accuracy and good real-time performance. However, the requirement of offline training a specific neural network results in the hardware source and time consumption. In order to improve the tracking efficiency and save computation resources, we adopt pre-trained densely connected neural network to extract robust target features. Since the pre-trained model is mainly used for classification task, it is not appropriate to directly adopt these deep features for visual tracking. We design a regression network to measure the importance of each channel to the target, and then propose a weighting fusion strategy to select the suitable features for visual tracking. Besides, we provide deep analysis about the proposed channel weighting method to demonstrate the superiority of this method through visualization of feature heatmaps. Extensive experiments on four classical benckmarks show that compared with state-of-the-art methods, our algorithm achieves the best results on several standard indicators and comparable results on other indicators. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of coordination bond and chain rigidity on the crystalline structure was discussed. • Novel polyimide films with low linear thermal expansion coefficients were made. • Mechanical Properties of polyimides were enhanced by introducing coordination bonds. Coordination bonds and chain rigidities play severe roles in crystalline structure and property of polyimides (PIs). This study developed various polyimides with metal-diimine coordination bonds and varying chain rigidities. How coordination bonds and chain stiffness affect the semi-crystalline structure of polyimide films was investigated. Results from Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) spectra confirmed the successful synthesis of coordinated polyimide films. Wide-angle diffraction (WAXD) results revealed that the crystallization behavior of PIs with flexible chains is significantly affected by additional coordination bonds, while the crystallization of PIs with rigid structures is primarily influenced by the chain rigidities. Compared to coordinated PIs with amorphous structure, PIs with both coordination bonds and semi-crystalline structures exhibited enhanced heat resistance, crystallinity, and dimensional stability. Notably, the coordinated PI-BP-Cu film with the highest chain rigidity in this study demonstrated excellent mechanical properties, with a tensile strength of 280 MPa, initial modulus of 5.7 GPa, and outstanding dimensional stability, characterized by a linear thermal expansion coefficient of 8.9 ppm/K (40–300 °C). These findings significantly enhance its suitability for use in metal/non-metal bonding composite materials. [ABSTRACT FROM AUTHOR]

Background: Pancreatic ductal adenocarcinoma (PDAC) is a devastatingly malignant tumor with a high mortality. However, current strategies to treat PDAC generally have low efficacy and high side-effects, therefore, effective treatment against PDAC remains an urgent need. Results: We report a semiconducting polymer nano-radiopharmaceutical with intrinsic photothermal capability and labeling with therapeutic radioisotope 177Lu (177Lu-SPN-GIP) for combined radio- and photothermal therapy of pancreatic tumor. 177Lu-SPN-GIP endowed good stability at physiological conditions, high cell uptake, and long retention time in tumor site. By virtue of combined radiotherapy (RT) and photothermal therapy (PTT), 177Lu-SPN-GIP exhibited enhanced therapeutic capability to kill cancer cells and xenograft tumor in living mice compared with RT or PTT alone. More importantly, 177Lu-SPN-GIP could suppress the growth of the tumor stem cells and reverse epithelial mesenchymal transition (EMT), which may greatly reduce the occurrence of metastasis. Conclusion: Such strategy we developed could improve therapeutic outcomes over traditional RT as it is able to ablate tumor with relatively lower doses of radiopharmaceuticals to reduce its side effects. [ABSTRACT FROM AUTHOR]

Background: Pancreatic ductal adenocarcinoma (PDAC) is a devastatingly malignant tumor with a high mortality. However, current strategies to treat PDAC generally have low efficacy and high side-effects, therefore, effective treatment against PDAC remains an urgent need. Results: We report a semiconducting polymer nano-radiopharmaceutical with intrinsic photothermal capability and labeling with therapeutic radioisotope 177Lu (177Lu-SPN-GIP) for combined radio- and photothermal therapy of pancreatic tumor. 177Lu-SPN-GIP endowed good stability at physiological conditions, high cell uptake, and long retention time in tumor site. By virtue of combined radiotherapy (RT) and photothermal therapy (PTT), 177Lu-SPN-GIP exhibited enhanced therapeutic capability to kill cancer cells and xenograft tumor in living mice compared with RT or PTT alone. More importantly, 177Lu-SPN-GIP could suppress the growth of the tumor stem cells and reverse epithelial mesenchymal transition (EMT), which may greatly reduce the occurrence of metastasis. Conclusion: Such strategy we developed could improve therapeutic outcomes over traditional RT as it is able to ablate tumor with relatively lower doses of radiopharmaceuticals to reduce its side effects. [ABSTRACT FROM AUTHOR]

Helical structures are attracting increasing attention owing to their unique typical physical and chemical properties. However, it remains a challenge to construct atypical helical structures at the microscale. This paper proposes a continuous spinning method with a microfluidic-chip-based spinning device to engineer atypical helical microfibers. The strategy causes polymer fluid to form the biomimetic Bulbine torta (BT)-like shape with the aid of the inhomogeneous viscosity rope-coil effect. In particular, the structure parameter of the BT microfibers could be optimized through the synchronous regulation of the microfluidic flow and reaction kinetics, and the obtained microfibers exhibit ultrahigh strain sensitivity, indicating great promise as exceptional candidates for constructing ideal strain sensors. In addition, single- and double-hollow BT microfibers are also prepared by introducing the core flow channel into the microfluidic chip and demonstrate high structural similarity to irregular blood vessels (e.g. varicose veins), which is promising for the actual application of blood vessel tissue engineering. [ABSTRACT FROM AUTHOR]

• A method to determine the productivity of ERC is proposed. • Dynamic model of roll was established. • Flow model of material in the crushing chamber was established. • Breakage model was established. Productivity, as one of the key indicators for assessing the performance of a crusher, holds significant importance in guiding production practices. It refers to the quantity of materials processed or the quality of output materials within a given time frame. However, there is currently limited research on eccentric roller crushers, and the calculation method for productivity is unclear, failing to consider the motion characteristics between the roller and the materials. To address these issues, this study analyses the motion mode of the crushing roller and establishes a dynamic model for the roll and a flow model for the material. Furthermore, a particle size distribution at the choke level has been established using the breakage model. Based on these models, a productivity calculation method for eccentric roll crushers is proposed. Then, the effectiveness of the method is verified through laboratory experiment. The results indicate that the proposed calculation method can effectively estimate the productivity of eccentric roll crushers. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Porous 3D nanofibrous scaffolds (TNSs) possess a rough surface, loose pore structure and excellent water absorption. • The TNSs could effectively enhance L929 cell adhesion, proliferation and migration behaviors compared to that of 2D mats. • The TNSs could significantly promote the wound healing compared with 2D mats in vivo. Abstract Too small pore size of electrospinning wound dressings limits cells of adjacent tissue to grow into the wound. Herein, a new aqueous phase fiber reassembly technology was addressed to fabricate polycaprolactone-polyethylene glycol-polycaprolactone (PCL-PEG-PCL) 3D nanofibrous scaffolds (TNSs) as a promising candidate for accelerating wound healing. The TNSs showed larger pore size with higher porosity compared with PCL-PEG-PCL 2D mats. The micron-sized hierarchical porous structure of TNSs enhanced water storage capacity, resulting in excellent water absorption. In addition, likely due to the rough surface and loose pore structure, the TNSs could effectively enhance L929 cell adhesion, proliferation and migration behaviors compared to that of 2D mats. Finally, in vivo tests supported the results of cellular experiments, TNSs could significantly promote the wound healing compared with 2D mats. [ABSTRACT FROM AUTHOR]

In this work, the water-soluble polyethyleneimine (PEI) was grafted onto the blended polystyrene (PS) and dopamine (PS/DA) electrospun fiber by using polydopamine (PDA) as an intermediate layer (PS/DA@PDA@PEI) to develop the water purification material toward Congo red (CR) dye removal. The morphology and structure of the obtained fibers were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Batch adsorption experiments were performed to investigate pH impacts, comparative adsorption, kinetics, isotherms, and thermodynamics. In comparison with PS/DA fibers and (PS/DA)@PDA fibers, the PS/DA@PDA@PEI fibers exhibited much higher CR adsorption capacity. The adsorption results also showed that the adsorption process toward CR by PS/DA@PDA@PEI fibers followed the Langmuir isotherm model and pseudo-second-order model. Meanwhile, the thermodynamic study revealed that CR removal was both spontaneous and endothermic. Further, the PS/DA@PDA@PEI loaded with CR can be recycled with HCl solution, which can be used repeatedly for CR adsorption. This work indicates that PS/DA@PDA@PEI fibers have great potential to be used as promising adsorbents for CR removal from water. [Display omitted] • A multifunctional (PS/DA)@PDA@PEI electrospinning nanofibrous membrane has been developed by firmly anchored PDA and PEI. • The modified nanofibrous membrane of (PS/DA)@PDA@PEI exhibited high efficiency as an adsorbent for GR removal. • Adsorption occurred mainly by electrostatic attraction and hydrogen bonding. • Isotherms, kinetic models, and thermodynamic parameters were investigated. [ABSTRACT FROM AUTHOR]

Constructing fully rigid chain polyimides with reversible sol-gel/gel-sol transition is significant for developing high-performance and functional materials. π-π stacking, a typical weak interaction, has attracted great interest in producing functional gels, but less has been reported in polyimide organogels. This work developed new polyimide organogels using π-π interactions by incorporating bisbenzoxazole moieties with fully coplanar structures in polyimides. The reversible sol-gel transition behavior with temperature and strain response was systematically studied using rheological methods. DFT simulations, temperature-dependent NMR, UV–Vis, and fluorescence spectroscopy results confirmed the existence of the dynamic π-π interactions in polyimides. Based on the success, we further combined sol-gel methods and non-solvent phase separation methods to prepare a new type of nanofiltration (NF) membranes. The resulting NF membranes showed a higher rejection of methylene blue (rejections of 99.6%) and a good permeability of sodium salt (rejections of 5.1–7.7%), showing great promise for selective filtration of industrial dye wastewater. [Display omitted] • Novel PI organogels were prepared by constructing π-π interactions. • NF membranes with good desalination ability were made. [ABSTRACT FROM AUTHOR]

The ability of autologous platelet-rich plasma (PRP) gel to promote rapid wound healing without immunological rejection has opened new avenues for the treatment of diabetic foot wounds. However, PRP gel still suffers from the quick release of growth factors (GFs) and requires frequent administration, thus resulting in decreased wound healing efficiency, higher cost as well as greater pain and suffering for the patients. In this study, the flow-assisted dynamic physical cross-linked coaxial microfluidic three-dimensional (3D) bio-printing technology, combined with the calcium ion chemical dual cross-linking method was developed to design PRP-loaded bioactive multi-layer shell-core fibrous hydrogels. The prepared hydrogels exhibited outstanding water absorption-retention capacity, good biocompatibility as well as a broad-spectrum antibacterial effect. Compared with clinical PRP gel, these bioactive fibrous hydrogels displayed a sustained release of GFs, reducing the administration frequency by 33 % availably during the wound treatment, but more prominent therapeutic effects such as effective reduced inflammation, in addition to promoting the growth of granulation tissue and angiogenesis, the formation of high-density hair follicles, and the generation of regular ordered and high-density collagen fiber network, which suggested great promise as exceptional candidates for treatment of diabetic foot ulcer in clinical settings. [Display omitted] • Bioactive gels based on Chitosan and Alginate, were designed by dual-cross-linked. • Gels exhibited good water absorption-retention, antibacterial and biocompatibility. • The steric hindrance effect of shell-core fibers prolong the release time of PRP. • Gels can reduced the frequency of administration by 33 %, and promoted wound healing. [ABSTRACT FROM AUTHOR]

Taking inspiration from the structures of roots, stems and leaves of trees in nature, a biomimetic three-layered scaffold was designed for efficient water management and cell recruitment. Using polycaprolactone (PCL) and polyacrylonitrile (PAN) as raw materials, radially oriented nanofiber films and multistage adjustable nanofiber films were prepared through electrospinning technology as the base skin-friendly layer (roots) and middle unidirectional moisture conductive material (stems), the porous polyurethane foam was integrated as the outer moisturizing layer (leaves). Among which, radially oriented nanofiber films could promote the directional migration of fibroblasts and induce cell morphological changes. For the spatially hierarchically nanofiber films, the unidirectional transport of liquid was effectively realized. While the porous polyurethane foam membrane could absorb 9 times its weight in biofluid and retain moisture for up to 10 h. As a result, the biomimetic three-layered scaffolds with different structures can promote wound epithelization and drain biofluid while avoiding wound inflammation caused by excessive biofluid, which is expected to be applied in the field of skin wounds. [Display omitted] ● Biomimetic three-layer scaffolds are composed of electrospun film and polyurethane film. ● Radially oriented nanofiber film can affect the behavior of L929 cells. ● Multistage structure nanofiber film has unidirectional water-transport capacity. ● Porous polyurethane foam film has superior water absorption and water retention. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel polyimide-based nanofiltration membranes were prepared by constructing dual coordination interactions. • The skin and supporting layers of NF membranes can be controlled by designing coordination interactions. • Nanofiltration membrane performance optimized by controllable microstructure. Polyimide-based nanofiltration membranes (NF) featuring customizable chemical structure and outstanding comprehensive performance have garnered tremendous interest for potential applications in ions rejection. Coordinated interactions can build supramolecular networks in polyimide that reshuffle phase separation behavior during membrane formation, thus conferring microstructural flexibility to nanofiltration membranes. In this paper, novel nanofiltration membranes were prepared by constructing dual coordination interactions in polyimide, and the structures were confirmed by NMR, FTIR, EDX, and XPS analyses. As expected, the skin and supporting layers of the PI-based NF membranes can be controlled by designing coordination conditions during membrane formation. A promising result is that the resulted NF membranes occur higher reject of metal ions than the pristine membranes prepared by conventional non-solvent induced phase separation methods. The optimized performance showed significantly higher permeability for removing Mg2+ ions, giving water permeance of 477.7 L m−2 h−1·bar−1 and a rejection of over 80%. Moreover, the resulted PI-based NF membranes occur better solvent resistance than the pristine NF membranes due to the enhanced coordination structures. As a preliminary study, this work gives a new strategy to regulate the microstructure of nanofiltration membranes, promising further potential for applications in ion removal. [ABSTRACT FROM AUTHOR]

Vehicle detection is a major part of a driver assistant system. However, a complex environment and diverse types of vehicles make real-time detection of vehicles a very challenging task. This paper proposes a real-time vehicle detection system of two steps: hypothesis generation and hypothesis verification. In the first step, potential vehicles are detected using shadows under vehicles. In the second step, hypotheses generated in the first step are classified as vehicles and non-vehicles. The novel aspect of this research is in constructing two types of histogram orientation gradients descriptors to extract vehicle features, and then combining them for their final features. The AdaBoost classifier is trained by the combined histogram orientation gradients features. The Treatment Group of images vehicle dataset is adopted for the classifier training. The experiment results show that the proposed system performs well in accuracy and robustness and can meet real-time requirements. [ABSTRACT FROM AUTHOR]

Nanofibrous dressings exhibit high specific surface areas, good histocompatibility, enhanced wound healing, and reduced inflammation, which have broad technological implications for treating diabetic foot ulcers (DFUs). However, current nanofibrous dressings still suffer from high resistance to cell infiltration and multiple dressing changes. In this study, polycaprolactone (PCL) and collagen were adopted as electrospinning materials to prepare a 3D PCL/Collagen (PC) nanofibrous dressing (3D-PC) using aqueous phase fibre reassembly technology. The matrix metalloproteinases (MMPs) inhibitor doxycycline hyclate (DCH)-loaded halloysite nanotubes (HNTs) (DCH@HNTs) and antibacterial agent cephalexin (CEX) were loaded onto the dressing to prepare a multifunctional 3D drug-loaded PCL/Collagen nanofibrous dressing to promote DFU wound healing. The obtained 3D nanofibrous dressing exhibited high water absorption capacity and swelling capacity. It showed good antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in vitro antibacterial test. In addition, the 3D nanofibrous dressing demonstrated good biocompatibility. It could significantly reduce the frequency of dressing changes and improve the healing of DFU wounds compared with the conventional multiple dressing changes method, suggesting a potential candidate for healing diabetic wounds. [Display omitted] • 3D PCL/Collagen nanofibrous dressing prepared using aqueous phase fibre reassembly technology. • 3D drug-loaded PCL/Collagen nanofibrous dressing has good antibacterial and biocompatibility. • 3D drug-loaded PCL/Collagen nanofibrous dressing reduces the need for dressing change to treat DFU wounds. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study is to evaluate the power, efficiency and emissions of an electronic-controlled single-cylinder engine fueled with pure natural gas and natural gas–hydrogen blends, respectively. Replacing the nature gas with hydrogen/methane blend fuels was found to have a significant influence on engine performance. The effects of excess air ratio and spark timing were discussed. The results show that under certain engine conditions the maximum cylinder gas pressure, maximum heat release rate increased with the increase of hydrogen fraction. The increase of hydrogen fraction in the blends contributed to the increase of NO x and the decrease of HC and CO. The brake specific fuel consumption decreased with the increase of hydrogen fraction. Using HCNG at relatively leaner fuel–air mixtures and retarded spark timing totally improved the engine emissions without incurring the performance penalty. [Copyright &y& Elsevier]