Yujie Chen

Preventing accidents caused by drowsiness has become a major focus of active safety driving in recent years. It requires an optimal technique to continuously detect drivers' cognitive state related to abilities in perception, recognition, and vehicle control in (near-) real-time. The major challenges in developing such a system include: 1) the lack of significant index for detecting drowsiness and 2) complicated and pervasive noise interferences in a realistic and dynamic driving environment. In this paper, we develop a drowsiness-estimation system based on electroencephalogram (EEG) by combining independent component analysis (ICA), power-spectrum analysis, correlation evaluations, and linear regression model to estimate a driver's cognitive state when he/she drives a car in a virtual reality (VR)-based dynamic simulator. The driving error is defined as deviations between the center of the vehicle and the center of the cruising lane in the lane-keeping driving task. Experimental results demonstrate the feasibility of quantitatively estimating drowsiness level using ICA-based multistream EEG spectra. The proposed ICA-based method applied to power spectrum of ICA components can successfully (1) remove most of EEG artifacts, (2) suggest an optimal montage to place EEG electrodes, and estimate the driver's drowsiness fluctuation indexed by the driving performance measure. Finally, we present a benchmark study in which the accuracy of ICA-component-based alertness estimates compares favorably to scalp-EEG based.

A hydrogel for potential applications in wound dressing should possess several peculiar properties, such as efficient self-healing ability and mechanical toughness, so as to repair muscle and skin damage. Additionally, excellent cell affinity and tissue adhesiveness are also necessary for the hydrogel to integrate with the wound tissue in practical applications. Herein, an ultratough and self-healing hydrogel with superior cell affinity and tissue adhesiveness is prepared. The self-healing ability of the hydrogel is obtained through hydrogen bonds and dynamic Schiff cross-linking between dopamine-grafted oxidized sodium alginate (OSA-DA) and polyacrylamide (PAM) chains. The covalent cross-linking is responsible for its stable mechanical structure. The combination of physical and chemical cross-linking contributes to a novel hydrogel with efficient self-healing ability (80% mechanical recovery in 6 h), high tensile strength (0.109 MPa), and ultrastretchability (2550%), which are highly desirable properties and are superior to previously reported tough and self-healing hydrogels for wound dressing applications. More remarkably, due to plenty of catechol groups on the OSA-DA chains, the hydrogel has unique cell affinity and tissue adhesiveness. Moreover, we demonstrate the practical utility of our fabricated hydrogel via both in vivo and in vitro experiments.

The combination of carbon materials and ferrite materials has recently attracted increased interest in microwave absorption applications. Herein, a novel composite with cobalt cores encapsulated in a porous carbon shell was synthesized via a facile sintering process with a cobaltic metal-organic framework (Co-MOF-74) as the precursor. Because of the magnetic loss caused by the Co cores and dielectric loss caused by the carbon shell with a unique porous structure, together with the interfacial polarization between two components, the ferromagnetic composite exhibited enhanced electromagnetic wave absorption performance compared to traditional ferrite materials. With the thermal decomposition temperature of 800 °C, the optimal reflection loss value achieved -62.12 dB at 11.85 GHz with thin thickness (2.4 mm), and the bandwidth ranged from 4.1 to 18 GHz with more than 90% of the microwave that could be absorbed. The achieved performance illustrates that the as-prepared porous Co-C core-shell composite shows considerable potential as an effective microwave absorber.

We have systematically investigated the impact of device size scaling on the light output, spectral shift, and self-heating of 400 nm InGaN light-emitting diodes (LEDs). Devices with diameters in the range 20–300 μm have been studied. It is shown that smaller LED pixels can deliver higher power densities (despite the lower absolute output powers) and sustain higher current densities. Investigations of the electroluminescence characteristics of differently sized pixels against current density reveal that the spectral shift is dominated by blueshift at the low current density level and then by redshift at the high current density level, owing to the competition between the bandgap shrinkage caused by self-heating and band-filling effects. The redshift of the emission wavelength with increasing current density is much faster and larger for the bigger pixels, suggesting that the self-heating effect is also size dependent. This is further confirmed by the junction-temperature rise measured by the established spectral shift method. It is shown that the junction-temperature rise in smaller pixels is slower, which in turn explains why the smaller redshift of the emission wavelength with current density is present in smaller pixels. The measured size-dependent junction temperature is in reasonable agreement with finite element method simulation results.

Topological quantum materials coupled with magnetism can provide a platform for realizing rich exotic physical phenomena, including quantum anomalous Hall effect, axion electrodynamics and Majorana fermions. However, these unusual effects typically require extreme experimental conditions such as ultralow temperature or sophisticate material growth and fabrication. Recently, new intrinsic magnetic topological insulators were proposed in MnBi2Te4-family compounds - on which rich topological effects could be realized under much relaxed experimental conditions. However, despite the exciting progresses, the detailed electronic structures observed in this family of compounds remain controversial up to date. Here, combining the use of synchrotron and laser light sources, we carried out comprehensive and high resolution angle-resolved photoemission spectroscopy studies on MnBi2Te4, and clearly identified its topological electronic structures including the characteristic gapless topological surface states. In addition, the temperature evolution of the energy bands clearly reveals their interplay with the magnetic phase transition by showing interesting differences for the bulk and surface states, respectively. The identification of the detailed electronic structures of MnBi2Te4 will not only help understand its exotic properties, but also pave the way for the design and realization of novel phenomena and applications.

The stable operation of the partial nitritation and anammox (PN/A) process is a challenge in the treatment of low-strength ammonia wastewater like sewage mainstream. This study demonstrated the feasibility of achieving stable operation in the treatment of 50 mg/L ammonia wastewater with a micro granule-based PN/A reactor. The long-term operation results showed nitrogen removal efficiencies of 71.8 ± 9.9% were stably obtained under a relatively short hydraulic retention time (HRT) of 2 h. The analysis on the physicochemical properties of the granules indicated most of the granules were in a size in a range of 265–536 μm, and the elementary composition of the granules was determined to be CH1.61O0.61N0.17S0.01P0.03. The microbial analysis revealed Candidatus Kuenenia stuttgartiensis anammox bacteria and Nitrosomonas-like AOB were the two most dominant bacteria with 27.6% and 10.5% abundance, respectively, both of which formed spatially syntrophic co-immobilization within the micro-granules. The ex-situ activity tests showed the activity of NOB was well limited through DO regulation in the reactor. These results provide an alternative PN/A process configuration for low-strength wastewater treatment by sustaining microstate granules. Optimization of the nitrogen sludge loading rate and DO regulation are important for the successful performance.

Multifunctional conductive hydrogels with representative preparation strategies and related properties.

Mode sorting is an essential function for optical multiplexing systems that exploit the orthogonality of the orbital angular momentum mode space. The familiar log-polar optical transformation provides a simple yet efficient approach whose resolution is, however, restricted by a considerable overlap between adjacent modes resulting from the limited excursion of the phase along a complete circle around the optical vortex axis. We propose and experimentally verify a new optical transformation that maps spirals (instead of concentric circles) to parallel lines. As the phase excursion along a spiral in the wave front of an optical vortex is theoretically unlimited, this new optical transformation can separate orbital angular momentum modes with superior resolution while maintaining unity efficiency.

Tissue engineering is an interdisciplinary field that integrates medical, biological, and engineering expertise to restore or regenerate the functionality of healthy tissues and organs. The three fundamental pillars of tissue engineering are scaffolds, cells, and biomolecules. Electrospun nanofibers have been successfully used as scaffolds for a variety of tissue engineering applications because they are biomimetic of the natural, fibrous extracellular matrix (ECM) and contain a three-dimensional (3D) network of interconnected pores. In this review, we provide an overview of the electrospinning process, its principles, and the application of the resultant electrospun nanofibers for tissue engineering. We first briefly introduce the electrospinning process and then cover its principles and standard equipment for biomaterial fabrication. Next, we highlight the most important and recent advances related to the applications of electrospun nanofibers in tissue engineering, including skin, blood vessels, nerves, bone, cartilage, and tendon/ligament applications. Finally, we conclude with current advancements in the fabrication of electrospun nanofiber scaffolds and their biomedical applications in emerging areas.

Electrospinning is a versatile strategy for creating nanofiber materials with various structures, which has broad application for a myriad of areas ranging from tissue engineering, energy harvesting, filtration and has become one of the most important academic and technical activities in the field of material science in recent years. In addition to playing a significant role in the construction of two-dimensional (2D) nanomaterials, electrospinning holds great promise as a robust method for producing three-dimensional (3D) aerogels and scaffolds. This article reviews and summarizes the recent advanced methods for fabricating electrospun three-dimensional nanofiber aerogels and scaffolds, including gas foaming, direct electrospinning of 3D nanofibrous scaffold, short nanofibers assembling into 3D aerogels/scaffolds, 3D printing, electrospray, origami and cell sheet engineering, centrifugal electrospinning, and other methods. Besides, intriguing formation process, crosslinking pathway, properties, and applications of 3D aerogels and scaffolds are also introduced. Taken together, these aerogels and scaffolds with various excellent features present tremendous potential in various fields.

Stimulus-responsive hydrogels, such as conductive hydrogels and thermoresponsive hydrogels, have been explored extensively and are considered promising candidates for smart materials such as wearable devices and artificial muscles. However, most of the existing studies on stimulus-responsive hydrogels have mainly focused on their single stimulus-responsive property and have not explored multistimulus-responsive or multifunction properties. Although some works involved multifunctionality, the prepared hydrogels were incompatible. In this work, a multistimulus-responsive and multifunctional hydrogel system (carboxymethyl cellulose/poly acrylic-acrylamide) with good elasticity, superior flexibility, and stable conductivity was prepared. The prepared hydrogel not only showed excellent human motion detection and physiological signal response but also possessed the ability to respond to environmental temperature changes. By integrating a conductive hydrogel with a thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) hydrogel to form a bilayer hydrogel, the prepared bilayer also functioned as two kinds of actuators owing to the different degrees of swelling and shrinking under different thermal stimuli. Furthermore, the different thermochromic properties of each layer in the bilayer hydrogel endowed the hydrogel with a thermoresponsive “smart” feature, the ability to display and conceal information. Therefore, the prepared hydrogel system has excellent prospects as a smart material in different applications, such as ionic skin, smart info-window, and soft robotics.

Abstract Multi‐environmental tolerant hydrogels have received significant attention and are promising for application as smart materials in multiple environments (e.g., water, oil, freezing, and dry). However, the macroscopic change and anti‐swelling mechanisms of organohydrogels in different solvents and their corresponding applications have not been adequately harnessed. Herein, an ionic organohydrogel with excellent mechanical properties and unique behaviors (information identification and encryption) and mechanical sensing in multiple environments is prepared. The prepared organohydrogel shows an obvious transparent change in different solvents owing to the microphase separation in poor solvents and swelling in suitable solvents, and can be treated as a dynamic information memory device for recording and encrypting information. Furthermore, owing to the interaction between water and dimethylsulfoxide (DMSO), the organohydrogel demonstrates a prominent freezing resistance (−90 to 20 °C) and moisturizing retention properties (76% after 15 days). In addition, the ionic conductive hydrogel exhibits outstanding human motion detection and physiological signal response and displays a stable mechanical sensing performance in freezing, dry conditions, and oil or water environments. It is envisioned that the design strategies and mechanistic investigation of organohydrogels may be promising for application as bio‐sensors and information‐recognition platforms in harsh environments.

Developing an excellent hemostatic material with good biocompatibility and high blood absorption capacity for rapid hemostasis of deep non-compressible hemorrhage remains a significant challenge. Herein, a novel conjugate electrospinning strategy to prepare an ultralight 3D gelatin sponge consisting of continuous interconnected nanofibers. This unique fluffy nanofiber structure endows the sponge with low density, high surface area, compressibility, and ultrastrong liquid absorption capacity. In vitro assessments show the gelatin nanofiber sponge has good cytocompatibility, high cell permeability, and low hemolysis ratio. The rat subcutaneous implantation studies demonstrate good biocompatibility and biodegradability of gelatin nanofiber sponge. Gelatin nanofiber sponge aggregates and activates platelets in large quantities to accelerate the formation of platelet embolism, and simultaneously escalates other extrinsic and intrinsic coagulation pathways, which collectively contribute to its superior hemostatic capacity. In vivo studies on an ear artery injury model and a liver trauma model of rabbits demonstrate that the gelatin nanofiber sponge rapidly induce stable blood clots with least blood loss compared to gelatin nanofiber membrane, medical gauze, and commercial gelatin hemostatic sponge. Hence, the gelatin nanofiber sponge holds great potential as an absorbable hemostatic agent for rapid hemostasis.

The advent of additive manufacturing (AM) offers the possibility of creating high-performance metallic materials with unique microstructure. Ultrafine dislocation cell structure in AM metals is believed to play a critical role in strengthening and hardening. However, its behavior is typically considered to be associated with alloying elements. Here we report that dislocations in AM metallic materials are self-stabilized even without the alloying effect. The heating–cooling cycles that are inherent to laser power-bed-fusion processes can stabilize dislocation network in situ by forming Lomer locks and a complex dislocation network. This unique dislocation assembly blocks and accumulates dislocations for strengthening and steady strain hardening, thereby rendering better material strength but several folds improvements in uniform tensile elongation compared to those made by traditional methods. The principles of dislocation manipulation and self-assembly are applicable to metals/alloys obtained by conventional routes in turn, through a simple post-cyclic deformation processing that mimics the micromechanics of AM. This work demonstrates the capability of AM to locally tune dislocation structures and achieve high-performance metallic materials.

Abstract Motivation Adverse drug–drug interactions (DDIs) are crucial for drug research and mainly cause morbidity and mortality. Thus, the identification of potential DDIs is essential for doctors, patients and the society. Existing traditional machine learning models rely heavily on handcraft features and lack generalization. Recently, the deep learning approaches that can automatically learn drug features from the molecular graph or drug-related network have improved the ability of computational models to predict unknown DDIs. However, previous works utilized large labeled data and merely considered the structure or sequence information of drugs without considering the relations or topological information between drug and other biomedical objects (e.g. gene, disease and pathway), or considered knowledge graph (KG) without considering the information from the drug molecular structure. Results Accordingly, to effectively explore the joint effect of drug molecular structure and semantic information of drugs in knowledge graph for DDI prediction, we propose a multi-scale feature fusion deep learning model named MUFFIN. MUFFIN can jointly learn the drug representation based on both the drug-self structure information and the KG with rich bio-medical information. In MUFFIN, we designed a bi-level cross strategy that includes cross- and scalar-level components to fuse multi-modal features well. MUFFIN can alleviate the restriction of limited labeled data on deep learning models by crossing the features learned from large-scale KG and drug molecular graph. We evaluated our approach on three datasets and three different tasks including binary-class, multi-class and multi-label DDI prediction tasks. The results showed that MUFFIN outperformed other state-of-the-art baselines. Availability and implementation The source code and data are available at https://github.com/xzenglab/MUFFIN.

Ligament injuries are common in sports and other rigorous activities. It is a great challenge to achieve ligament regeneration after an injury due the avascular structure and low self-renewal capability. Herein, we developed vascular endothelial growth factor (VEGF)-binding aligned electrospun poly(caprolactone)/gelatin (PCL/Gel) scaffolds by incorporating prominin-1-binding peptide (BP) sequence and exploited them for patellar ligament regeneration. The adsorption of BP onto scaffolds was discerned by various techniques, such as Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and confocal laser scanning microscope. The accumulation of VEGF onto scaffolds correlated with the concentration of the peptide in vitro. BP-anchored PCL/Gel scaffolds (BP@PCL/Gel) promoted the tubular formation of human umbilical vein endothelial cells (HUVECs) and wound healing in vitro. Besides, BP containing scaffolds exhibited higher content of CD31+ cells than that of the control scaffolds at 1 week after implantation in vivo. Moreover, BP containing scaffolds improved biomechanical properties and facilitated the regeneration of matured collagen in patellar ligament 4 weeks after implantation in mice. Overall, this strategy of peptide-mediated orchestration of VEGF provides an enticing platform for the ligament regeneration, which may also have broad implications for tissue repair applications. STATEMENT OF SIGNIFICANCE: Ligament injuries are central to sports and other rigorous activities. Given to the avascular nature and poor self-healing capability of injured ligament tissues, it is a burgeoning challenge to fabricate tissue-engineered scaffolds for ligament reconstruction. Vascular endothelial growth factor (VEGF) is pivotal to the neo-vessel formation. However, the high molecular weight of VEGF as well as its short half-life in vitro and in vivo limits its therapeutic potential. To circumvent these limitations, herein, we functionalized aligned electrospun polycaprolactone/gelatin (PCL/Gel)-based scaffolds with VEGF-binding peptide (BP) and assessed their biocompatibility and performance in vitro and in vivo. BP-modified scaffolds accumulated VEGF, improved tube formation of HUVECs, and induced wound healing in vitro, which may have broad implications for regenerative medicine and tissue engineering.

Cardiovascular disease has become the leading cause of death. A vascular stent is an effective means for the treatment of cardiovascular diseases. In recent years, biodegradable polymeric vascular stents have been widely investigated by researchers because of its degradability and clinical application potential for cardiovascular disease treatment. Compared to non-biodegradable stents, these stents are designed to degrade after vascular healing, leaving regenerated healthy arteries. This article reviews and summarizes the recent advanced methods for fabricating biodegradable polymeric stents, including injection molding, weaving, 3D printing, and laser cutting. Besides, the functional modification of biodegradable polymeric stents is also introduced, including visualization, anti-thrombus, endothelialization, and anti-inflammation. In the end, the challenges and future perspectives of biodegradable polymeric stents were discussed.

Food preservation is important in increasing the shelf life of food and ensuring food safety. Investigations on food preservation have focused on meeting consumer demands for more natural and healthier food. Bacteriocins produced by lactic acid bacteria have caught the attention of food scientists to be used as natural food biopreservatives due to their antimicrobial activity against food spoilage and pathogenic bacteria. Class II bacteriocins are the largest bacteriocin family of lactic acid bacteria but have received disproportionately less attention than class I bacteriocins. This article systematically compared the sequence property, 3-D structure, and mode of action of the four categories of class II bacteriocins of lactic acid bacteria. The current and potential applications of class II bacteriocins in the food industry have also been reviewed. A SWOT (Strength, Weaknesses, Opportunities and Threats) analysis of the different approaches and development on class II bacteriocins was performed. The class II bacteriocins produced by lactic acid bacteria have a variety of sequences and diverse properties, structures, and modes of action. Some of class II bacteriocins, e.g. pediocin, enterocin AS-48, plantaricin EF, are considered as attractive compounds in the food industry to prevent food spoilage and pathogenic bacterial growth. Elucidation of their characteristics and modes of action provides fundamental information in designing novel application strategies. The SWOT analysis will be helpful for current and future researches on class II bacteriocins. • The four sub-categories of class II bacteriocins of lactic acid bacteria have distinct properties. • Class II bacteriocins exert antimicrobial activity through receptor recognition and/or electrostatic interaction. • Class II bacteriocins are attractive antimicrobial compounds and have great potential in the food industry. • A SWOT analysis on the development and application of classII bacteriocins has been performed.

Because intelligent hydrogels have good biocompatibility, a rapid response, and good degradability as well as a stimulus response mode that is rich, hydrophilic, and similar to the softness and elasticity of living tissue, they have received widespread attention and are widely used in biomedical engineering. In this article, we conduct a systematic review of the use of smart hydrogels in biomedical engineering. First, we introduce the properties and applications of hydrogels and compare the similarities and differences between traditional hydrogels and smart hydrogels. Secondly, we summarize the intelligent hydrogel types, the mechanisms of action used by different hydrogels, and the materials for preparing different types of hydrogels, such as the materials for the preparation of temperature-responsive hydrogels, which mainly include gelatin, carrageenan, agarose, amylose, etc.; summarize the morphologies of different hydrogels, such as films, fibers and microspheres; and summarize the application of smart hydrogels in biomedical engineering, such as for the delivery of proteins, antibiotics, deoxyribonucleic acid, etc. Finally, we summarize the shortcomings of current research and present future prospects for smart hydrogels. The purpose of this paper is to provide researchers engaged in related fields with a systematic review of the application of intelligent hydrogels in biomedical engineering. We hope that they will get some inspiration from this work to provide new directions for the development of related fields.

The compositional heterogeneity in high-entropy alloys (HEAs) has been reported to be an inherent entity, which significantly alters the mechanical properties of materials by tuning the variation of lattice resistance for dislocation motion. However, since the body-centered cubic (BCC) structure is not close-packed, the change of lattice resistance is less sensitive to the normal concentration wave compared to that in face-centered cubic (FCC) structured materials. In this work, we selected a refractory bcc HEAs TiZrNbTa for the matrix and added a small amount of Al to facilitate the special spinodal decomposition structure. In particular, (TiZrNbTa)98.5Al1.5 displayed a typical basket-weave fabric morphology of spinodal decomposition structure with a characteristic periodicity of ∼8 nm and had an optimal combination of strength and ductility (the yield strength of 1123 ± 9 MPa and ductility of ∼20.7% ± 0.6%). It was determined that by doing in situ TEM mechanical testing, the plastic deformation was dominated by the formation and operation of dislocation loops which provided both edge and screw components of dislocations. The synergetic effect of the remarkable chemical heterogeneity created by the spinodal decomposition and the spreading lattice distortion in high entropy alloys is quite effective in tuning the mobility of different types of dislocations and facilitates dislocation interactions, enabling the combination of high strength and ductility.

The escalating global demand for chemicals and energy, coupled with the rising carbon emissions resulting from the extraction and combustion of fossil fuels, has had detrimental effects on the environment. In light of these challenges, the utilization of biomass has emerged as a viable solution that offers both environmental and economic benefits. Biomass-derived formic acid and acetic acid are two prominent chemicals with diverse applications in the chemical and energy industries, and numerous environmentally benign and efficient conversion technologies have been developed for their production. However, comprehensive reviews that encompass the existing technologies, recent advancements, and the exploration of novel biomass resources are scant. Therefore, this paper provides a comprehensive review of the various technologies developed for the conversion of biomass into formic acid and acetic acid. The review covers not only traditional hydrothermal wet oxidation and catalytic oxidation methods, but also highlights the recent progress in emerging electro- and photocatalytic methods. Furthermore, different types of biomass, including carbohydrate biomass and lignocellulosic biomass from agroforestry, as well as chitin-based and microalgae biomass from the ocean, which hold promising potential for biomass utilization, are classified and discussed. This paper underscores the significant development potential of producing formic acid and acetic acid through the conversion of recyclable biomass.

Osteoarthritis (OA) is one of the most common chronic musculoskeletal diseases, which accounts for a large proportion of physical disabilities worldwide. Herein, we fabricated injectable gelatin/poly(L-lactide)-based nanofibrous microspheres (MS) via electrospraying technology, which were further modified with tannic acid (TA) named as TMS or metal phenolic networks (MPNs) consisting of TA and strontium ions (Sr2+) and named as TSMS to enhance their bioactivity for OA therapy. The TA-modified microspheres exhibited stable porous structure and anti-oxidative activity. Notably, TSMS showed a sustained release of TA as compared to TMS, which exhibited a burst release of TA. While all types of microspheres exhibited good cytocompatibility, TSMS displayed good anti-inflammatory properties with higher cell viability and cartilage-related extracellular matrix (ECM) secretion. The TSMS microspheres also showed less apoptosis of chondrocytes in the hydrogen peroxide (H2O2)-induced inflammatory environment. The TSMS also inhibited the degradation of cartilage along with the considerable repair outcome in the papain-induced OA rabbit model in vivo as well as suppressed the expression level of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-1-beta (IL-1β). Taken together, TSMS may provide a highly desirable therapeutic option for intra-articular treatment of OA. STATEMENT OF SIGNIFICANCE: Osteoarthritis (OA) is a chronic disease, which is caused by the inflammation of joint. Current treatments for OA achieve pain relief but hardly prevent or slow down the disease progression. Microspheres are at the forefront of drug delivery and tissue engineering applications, which can also be minimal-invasively injected into the joint. Polyphenols and therapeutic ions have been shown to be beneficial for the treatment of diseases related to the joints, including OA. Herein, we prepared gelatin/poly(L-lactide)-based nanofibrous microspheres (MS) via electrospinning incorporated electrospraying technology and functionalized them with the metal phenolic networks (MPNs) consisting of TA and strontium ions (Sr2+), and assessed their potential for OA therapy both in vitro and in vivo.

A major challenge in artificial intelligence based ECG diagnosis lies that it is difficult to obtain sufficient annotated training samples for each rhythm type, especially for rare diseases, which makes many approaches fail to achieve the desired performance with limited ECG records. In this paper, we propose a Meta Siamese Network (MSN) based on metric learning to achieve high accuracy for automatic ECG arrhythmias diagnosis with limited ECG records. First, the ECG signals from three different ECG datasets are preprocessed through resampling, wavelet denoising, R-wave localization, heartbeat segmentation and Z-score normalization. Then, an ECG dataset with limited records is constructed to verify the performance of the proposed model and explore variation of model performance with the sample size. Second, a metric-based meta-learning framework is proposed to address the challenge of few-shot learning for automatic ECG diagnosis of cardiac arrhythmia, and siamese network is employed to achieve arrhythmia diagnosis based on similarity metric. Finally, the N-way K-shot meta-testing strategy is proposed based on the siamese network with double inputs, and the experimental results demonstrate that the proposed strategy can effectively improve the robustness of the proposed model.

Anammox is attracting attention as the most promising nitrogen removal technology. Recently, the combination of the anammox process and the hydroxyapatite (HAP) granules comes with the advantages, including simultaneous removals of nitrogen and phosphorus and better settleability of the sludge. In this study, the key factors for a stable and efficient nitrogen removal in a one-stage partial nitritation/anammox (PNA) process with HAP-based granules was explored. Under a fixed hydraulic retention time of 12 h, in the case that HAP was not properly formed and phosphorus removal efficiency (PRE) was low, the highest nitrogen removal rate (NRR) achieved stably was only 1.3 ± 0.07 kg N/m3/d, while a stable nitrogen removal efficiency of 81 ± 3.3 % and a higher NRR of 2.0 ± 0.1 kg N/m3/d were obtained with the proper formation of HAP and higher PRE. The achievement of the high NRR benefited by a high microorganism concentration with improved settleability due to the formation of HAP-based granules. To achieve a high NRR in a long-term operation, a necessary phosphorus removal rate/nitrogen removal rate ratio above 0.02 was confirmed, which allowed for the desired sludge settleability and concentration. The average diameter of the formed micro-granules was 92–159 μm. The spatial distribution of the functional bacteria in the granules was analyzed with fluorescence in situ hybridization. Anammox bacteria and the ammonium oxidizing bacteria the two most abundant bacteria during the whole operation. The results of this study are evidence of the necessity and potential of proportionable HAP formation for highly-efficient nitrogen removal in the one-stage PNA process.

Abstract [1] Ground-based validation is crucial for ensuring the accuracy of remotely sensed evapotranspiration (RS_ET) and extending its application. This paper proposes an innovative validation method based on multisource evapotranspiration (ET) from ground measurements, with the validation results including the accuracy assessment, error source analysis, and uncertainty analysis of the validation process. It is a potentially useful approach to evaluate the accuracy and analyze the spatiotemporal properties of RS_ET at both the basin and local scales, and is appropriate to validate RS_ET in diverse resolutions at different time-scales. An independent RS_ET validation using such a method was presented over the Hai River Basin in 2002–2009, China. In general, validation at the basin scale showed good agreements between the 1 km annual RS_ET and the validation data such as the water balance ET (root-mean-square error (RMSE): 50.73 mm), MODIS ET products (RMSE: 79.84 mm), precipitation, and land use types. At the local scale, multiscale ET measurements from large aperture scintillometer (LAS) and eddy covariance system (EC) with a footprint model were used for validation over three typical landscapes. In most cases, the 1 km RS_ET resulted in slight overestimation with the LAS measurements (RMSE: 10.75 mm for monthly results, 0.78 mm for daily results), while the 30 m RS_ET was underestimated compared to the EC measurements (RMSE: 16.28 mm for monthly results, 0.99 mm for daily results). Furthermore, error sources of RS_ET and uncertainties of the validation process were investigated in detail. The results showed that the proposed validation method was reasonable and feasible.

Protein folding is a fundamental process in biology, key to understanding many human diseases. Experimentally, proteins often appear to fold via simple two- or three-state mechanisms involving mainly native-state interactions, yet recent network models built from atomistic simulations of small proteins suggest the existence of many possible metastable states and folding pathways. We reconcile these two pictures in a combined experimental and simulation study of acyl-coenzyme A binding protein (ACBP), a two-state folder (folding time ~10 ms) exhibiting residual unfolded-state structure, and a putative early folding intermediate. Using single-molecule FRET in conjunction with side-chain mutagenesis, we first demonstrate that the denatured state of ACBP at near-zero denaturant is unusually compact and enriched in long-range structure that can be perturbed by discrete hydrophobic core mutations. We then employ ultrafast laminar-flow mixing experiments to study the folding kinetics of ACBP on the microsecond time scale. These studies, along with Trp-Cys quenching measurements of unfolded-state dynamics, suggest that unfolded-state structure forms on a surprisingly slow (~100 μs) time scale, and that sequence mutations strikingly perturb both time-resolved and equilibrium smFRET measurements in a similar way. A Markov state model (MSM) of the ACBP folding reaction, constructed from over 30 ms of molecular dynamics trajectory data, predicts a complex network of metastable stables, residual unfolded-state structure, and kinetics consistent with experiment but no well-defined intermediate preceding the main folding barrier. Taken together, these experimental and simulation results suggest that the previously characterized fast kinetic phase is not due to formation of a barrier-limited intermediate but rather to a more heterogeneous and slow acquisition of unfolded-state structure.

We report random laser action in a system where optical amplification is provided by colloidal quantum dots (CQDs). This system is obtained by depositing from solution CdSe/ZnS core-shell CQDs into rough micron-scale grooves fabricated on the surface of a glass substrate. The combination of CQD random packing and of disordered structures in the glass groove enables gain and multiple scattering. Upon optical excitation, random laser action is triggered in the system above a 25-mJ/cm2 threshold. Single-shot spectra were recorded to study the emission spectral characteristics and the results show the stability of the laser mode positions and the dominance of the modes close to the material gain maximum.

Abstract An improved approach to assemble ultrathin and thickness-tunable polypyrrole (PPy) films onto multiwall carbon nanotubes (MWCNTs) has been investigated. A facile procedure is demonstrated for controlling the morphology and thickness of PPy film by adding ethanol in the reaction system and a possible mechanism of the coating formation process is proposed. The coated PPy films can be easily tuned by adding ethanol and adjusting a mass ratio of pyrrole to MWCNTs. Moreover, the thickness of PPy significantly influences the electronic conductivity and capacitive behavior of the PPy/MWCNT composites. The method may provide a facile strategy for tailoring the polymer coating on carbon nanotubes (CNTs) for carbon-based device applications.

A fractional-order fuzzy logic control (FOFLC) method for maximum power point tracking (MPPT) in a photovoltaic (PV) system is presented. By combining the robustness of fuzzy logic with the accuracy of fractional order, the proposed method can improve the tracking accuracy in weather variations compared with the conventional fuzzy MPPT. First, the fractional-order factor is carefully selected according to the dynamic range of the fuzzy controller. It takes a bigger alpha factor in the first place to expand the fuzzy domain and shortens the time of searching for the MPP. When the maximum power point is approached, it uses a smaller the alpha factor to contract the fuzzy domain and eliminates the oscillations at the MPP. Therefore, the FOFLC in a PV system has rapid dynamic responses under environment variations and high tracking accuracy of the maximum power point. Second, MATLAB/Simulink software is employed to simulate a PV power system and verify the proposed algorithm by various simulations. The enhanced MPPT algorithm has been implemented on a field programmable gate array (FPGA) board. Finally, a boost dc-dc converter experiment has been carried out to evaluate the system performance. The simulation and experiment results show that this method can improve the transient and steady-state performance simultaneously.

We propose and demonstrate a scalable mode division multiplexing scheme based on orbital angular momentum modes in ring core fibers. In this scheme, the high-order mode groups of a ring core fiber are sufficiently de-coupled by the large differential effective refractive index so that multiple-input multiple-output (MIMO) equalization is only used for crosstalk equalization within each mode group. We design and fabricate a graded-index ring core fiber that supports 5 mode groups with low inter-mode-group coupling, small intra-mode-group differential group delay, and small group velocity dispersion slope over the C-band for the high-order mode groups. We implement a two-dimensional wavelength- and mode-division multiplexed transmission experiment involving 10 wavelengths and 2 mode groups each with 4 OAM modes, transmitting 32 GBaud Nyquist QPSK signals over all 80 channels. An aggregate capacity of 5.12 Tb/s and an overall spectral efficiency of 9 bit/s/Hz over 10 km are realized, only using modular 4x4 MIMO processing with 15 taps to recover signals from the intra-mode-group mode coupling. Given the fixed number of modes in each mode group and the low inter-mode-group coupling in ring core fibres, our scheme strikes a balance in the trade-off between system capacity and digital signal processing complexity, and therefore has good potential for capacity upscaling at an expense of only modularly increasing the number of mode-groups with fixed-size (4x4) MIMO blocks.

Haematopoietic stem and progenitor cells (HSPCs) give rise to all blood lineages that support the entire lifespan of vertebrates1. After HSPCs emerge from endothelial cells within the developing dorsal aorta, homing allows the nascent cells to anchor in their niches for further expansion and differentiation2-5. Unique niche microenvironments, composed of various blood vessels as units of microcirculation and other niche components such as stromal cells, regulate this process6-9. However, the detailed architecture of the microenvironment and the mechanism for the regulation of HSPC homing remain unclear. Here, using advanced live imaging and a cell-labelling system, we perform high-resolution analyses of the HSPC homing in caudal haematopoietic tissue of zebrafish (equivalent to the fetal liver in mammals), and reveal the role of the vascular architecture in the regulation of HSPC retention. We identify a VCAM-1+ macrophage-like niche cell population that patrols the inner surface of the venous plexus, interacts with HSPCs in an ITGA4-dependent manner, and directs HSPC retention. These cells, named 'usher cells', together with caudal venous capillaries and plexus, define retention hotspots within the homing microenvironment. Thus, the study provides insights into the mechanism of HSPC homing and reveals the essential role of a VCAM-1+ macrophage population with patrolling behaviour in HSPC retention.

With the amplitude, time, wavelength/frequency, phase, and polarization/spin parameter dimensions of the light wave/photon almost fully utilized in both classical and quantum photonic information systems, orbital angular momentum (OAM) carried by optical vortex modes is regarded as a new modal parameter dimension for further boosting the capacity and performance of the systems. To exploit the OAM mode space for such systems, stringent performance requirements on a pair of OAM mode multiplexer and demultiplexer (also known as mode sorters) must be met. In this work, we implement a newly discovered optical spiral transformation to achieve a low-cross-talk, wide-optical-bandwidth, polarization-insensitive, compact, and robust OAM mode sorter that realizes the desired bidirectional conversion between seven co-axial OAM modes carried by a ring-core fiber and seven linearly displaced Gaussian-like modes in parallel single-mode fiber channels. We further apply the device to successfully demonstrate high-spectral-efficiency and high-capacity data transmission in a 50-km OAM fiber communication link for the first time, in which a multi-dimensional multiplexing scheme multiplexes eight orbital-spin vortex mode channels with each mode channel simultaneously carrying 10 wavelength-division multiplexing channels, demonstrating the promising potential of both the OAM mode sorter and the multi-dimensional multiplexed OAM fiber systems enabled by the device. Our results pave the way for future OAM-based multi-dimensional communication systems.

Mix-and-inject serial crystallography (MISC) is a technique designed to image enzyme catalyzed reactions in which small protein crystals are mixed with a substrate just prior to being probed by an X-ray pulse. This approach offers several advantages over flow cell studies. It provides (i) room temperature structures at near atomic resolution, (ii) time resolution ranging from microseconds to seconds, and (iii) convenient reaction initiation. It outruns radiation damage by using femtosecond X-ray pulses allowing damage and chemistry to be separated. Here, we demonstrate that MISC is feasible at an X-ray free electron laser by studying the reaction of M. tuberculosis ß-lactamase microcrystals with ceftriaxone antibiotic solution. Electron density maps of the apo-ß-lactamase and of the ceftriaxone bound form were obtained at 2.8 Å and 2.4 Å resolution, respectively. These results pave the way to study cyclic and non-cyclic reactions and represent a new field of time-resolved structural dynamics for numerous substrate-triggered biological reactions.

Serial femtosecond crystallography requires reliable and efficient delivery of fresh crystals across the beam of an X-ray free-electron laser over the course of an experiment. We introduce a double-flow focusing nozzle to meet this challenge, with significantly reduced sample consumption, while improving jet stability over previous generations of nozzles. We demonstrate its use to determine the first room-temperature structure of RNA polymerase II at high resolution, revealing new structural details. Moreover, the double-flow focusing nozzles were successfully tested with three other protein samples and the first room temperature structure of an extradiol ring-cleaving dioxygenase was solved by utilizing the improved operation and characteristics of these devices [corrected].

We report the first demonstration of a direct interaction between the extraordinary transverse spin angular momentum in evanescent waves and the intrinsic orbital angular momentum in optical vortex beams. By tapping the evanescent wave of whispering gallery modes in a micro-ring-based optical vortex emitter and engineering the transverse spin state carried therein, a transverse-spin-to-orbital conversion of angular momentum is predicted in the emitted vortex beams. Numerical and experimental investigations are presented for the proof-of-principle demonstration of this unconventional interplay between the spin and orbital angular momenta, which could provide new possibilities and restrictions on the optical angular momentum manipulation techniques on the sub-wavelength scale. This phenomenon further gives rise to an enhanced spin-direction coupling effect in which waveguide or surface modes are unidirectional excited by incident optical vortex, with the directionality jointly controlled by spin-orbit states. Our results enrich the spin-orbit interaction phenomena by identifying a previously unknown pathway between the polarization and spatial degrees of freedom of light, and can enable a variety of functionalities employing spin and orbital angular momenta of light in applications such as communications and quantum information processing.

Emerging studies have demonstrated the important physiological and pathophysiological roles of hydrogen sulphide (H2S) as a gasotransmitter for NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome-associated neuroinflammation in the central nervous system. However, the effects of H2S on neuroinflammation after intracerebral haemorrhage (ICH), especially on the NLRP3 inflammasome, remain unknown.We employed a Sprague-Dawley rat of collagenase-induced ICH in the present study. The time course of H2S content and the spatial expression of cystathionine-β-synthase (CBS) after ICH, the effects of endogenous and exogenous H2S after ICH, the effects of endogenous and exogenous H2S on NLRP3 inflammasome activation under P2X7 receptor (P2X7R) overexpression after ICH, and the involvement of the P2X7R in the mechanism by which microglia-derived H2S prevented NLRP3 inflammasome activation were investigated.We found ICH induced significant downregulation of endogenous H2S production in the brain, which may be the result of decreasing in CBS, the predominant cerebral H2S-generating enzyme. Administration of S-adenosyl-L-methionine (SAM), a CBS-specific agonist, or sodium hydrosulfide (NaHS), a classical exogenous H2S donor, not only restored brain and plasma H2S content but also attenuated brain oedema, microglial accumulation and neurological deficits at 1 day post-ICH by inhibiting the P2X7R/NLRP3 inflammasome cascade. Endogenous H2S production, which was derived mainly by microglia and above treatments, was verified by adenovirus-overexpressed P2X7R and in vitro primary microglia studies.These results indicated endogenous H2S synthesis was impaired after ICH, which plays a pivotal role in the P2X7R/NLRP3 inflammasome-associated neuroinflammatory response in the pathogenesis of secondary brain injury. Maintaining appropriate H2S concentrations in the central nervous system may represent a potential therapeutic strategy for managing post-ICH secondary brain injury and associated neurological deficits.

This paper presents a model of a hybrid electric vehicle, based on a primary proton exchange membrane fuel cell (PEMFC) and an auxiliary Li-ion battery, and its dynamics and overall performance. The power voltage from the fuel cell is regulated by a DC/DC converter before integrating with the Li-ion battery, which provides energy to the drive motor. The driving force for propelling the wheels comes from a permanent magnet synchronous motor (PMSM); where the power passes through the transmission, shaft, and the differential. The mathematical model, comprising the PEMFC, Li-ion battery, PMSM, and vehicular structure, was modeled in MATLAB/Simulink. A power management model was incorporated in the system such that the power output varies in different conditions; including high power, low power, standard power, and charge modes. By changing the speed of the accelerator, the relation between the output of dual power supply, hydrogen consumption, and Li-ion battery’s state of charge was observed. The power management model is validated against the ECE40 driving cycle. The performance of the fuel cell hybrid vehicle is evaluated. The operation modes in the vehicle show a close match with the proposed power management system. Additionally, the hybrid ratio is measured to evaluate the overall efficiency. The results indicate that the hybrid ratio shows little correlation with efficiency. However, the higher the power of the fuel cell, the higher the hydrogen consumption.

Deep eutectic solvents (DESs) have potential applications in biomass conversion and green chemicals due to their cost-effectiveness and environmentally friendly properties. This study reports on a feasible method of using DESs for lignin selective extraction from poplar wood meal. DESs obtained from various hydrogen-bond donors and acceptors were used to evaluate the dissolving capacity of lignin from poplar wood meal. Among the various DESs, lactic acid: choline chloride (9 : 1) exhibits the optimal extraction capacity, which is capable of selectively dissolving 95% of lignin from poplar wood meal at 120°C for 6 h. The purity of isolated lignin reaches 98% after regeneration in water. From Fourier Transform-IR, nitrobenzene oxidation and nuclear magnetic resonance analysis, the results demonstrate that the DESs can selectively cleave ether linkages and damage the non-condensation section of lignin, thereby facilitating lignin dissolution from wood meal. Thus, this study provides a promising route for the extraction of high-purity lignin from biomass materials.

Abstract New polyurethane‐based polycaprolactone copolymer networks, with shape recovery properties, are presented here. Once deformed at ambient temperature, they show 100% shape fixation until heated above the melting point, where they recover the initial shape within 22 s. In contrast to current shape memory materials, the new materials do not require deformation at elevated temperature. The stable polymer structure of polyurethane yields a copolymer network that has strength of 10 MPa with an elongation at break of 35%. The copolymer networks are self‐healing at a slightly elevated temperature (70 °C) without any external force, which is required for existing self‐healing materials. This allows for the new materials to have a long life of repeated healing cycles. The presented copolymers show features that are promising for applications as temperature sensors and activating elements.

Remarkable progress achieved for conductive hydrogels has been witnessed in recent years. However, hydrogels are easily damaged during the course of use, which limits their applications as soft conductors. Here, the nanocomposite hydrogels with fast self-healing property, conductive capability and strain-sensitive performance are successfully obtained via simple synthesis routes. Dynamic diol-borate eater bonds built from polyvinyl alcohol (PVA) and borax mainly allow nanocomposite hydrogels to display decent self-healing behaviors in mechanical (restore 92.89% of original tensile strength within 60 s), electrical (restore 96.7 ± 2% of original resistance within 4.2 s) and rheological recovery experiments without any external stimuli. Meanwhile, hydrogen bonds in prepared networks can endow hydrogels with self-healing property to a certain extent. Graphene oxide (GO) is partially reduced under the oxidative self-polymerization of dopamine (DA), providing conductivity for nanocomposite hydrogels (2.7 mS cm−1). Besides, the mechanical property and conductivity of nanocomposite hydrogels are controlled by the reduction degree of GO. Due to physical interactions formed among oxygen functional groups, the nanocomposite hydrogels show greater behaviors in mechanical, rheological and swelling tests verse pure PVA hydrogels. Furthermore, the acquired hydrogels demonstrate strain sensitivity in the designed LED bulb circuit. In view of no apparent anaphylaxis of nanocomposite hydrogels to human skins, the soft stain sensor prepared by designed hydrogel can be fabricated to detect human activities, such as bending and sitting. Our work offers an effective approach to synthesize a fast self-healing, conductive and strain-sensitive hydrogel applied as soft strain sensor for human movement monitoring.

The abnormal self-assembly of amyloid-β (Aβ) peptides into toxic fibrillar aggregates is associated with the pathogenesis of Alzheimer's disease (AD). The inhibition of β-sheet-rich oligomer formation is considered as the primary therapeutic strategy for AD. Previous experimental studies reported that norepinephrine (NE), one of the neurotransmitters, is able to inhibit Aβ aggregation and disaggregate the preformed fibrils. Moreover, exercise can markedly increase the level of NE. However, the underlying inhibitory and disruptive mechanisms remain elusive. In this work, we performed extensive replica-exchange molecular dynamic (REMD) simulations to investigate the conformational ensemble of Aβ1-42 dimer with and without NE molecules. Our results show that without NE molecules, Aβ1-42 dimer transiently adopts a β-hairpin-containing structure, and the β-strand regions of this β-hairpin (residues 15QKLVFFA21 and 33GLMVGGVV40) strongly resemble those of the Aβ fibril structure (residues 15QKLVFFA21 and 30AIIGLMVG37) reported in an electron paramagnetic resonance spectroscopy study. NE molecules greatly reduce the interpeptide β-sheet content and suppress the formation of the above-mentioned β-hairpin, leading to a more disordered coil-rich Aβ dimer. Five dominant binding sites are identified, and the central hydrophobic core 16KLVFFA21 site and C-terminal 31IIGLMV36 hydrophobic site are the two most favorable ones. Our data reveal that hydrophobic, aromatic stacking, hydrogen-bonding and cation-π interactions synergistically contribute to the binding of NE molecules to Aβ peptides. MD simulations of Aβ1-42 protofibril show that NE molecules destabilize Aβ protofibril by forming H-bonds with residues D1, A2, D23, and A42. This work reveals the molecular mechanism by which NE molecules inhibit Aβ1-42 aggregation and disaggregate Aβ protofibrils, providing valuable information for developing new drug candidates and exercise therapy against AD.

Microrobotics extends the reach of human-controlled machines to submillimeter dimensions. We introduce a microrobot that relies on optoelectronic tweezers (OET) that is straightforward to manufacture, can take nearly any desirable shape or form, and can be programmed to carry out sophisticated, multiaxis operations. One particularly useful program is a serial combination of "load," "transport," and "deliver," which can be applied to manipulate a wide range of micrometer-dimension payloads. Importantly, microrobots programmed in this manner are much gentler on fragile mammalian cells than conventional OET techniques. The microrobotic system described here was demonstrated to be useful for single-cell isolation, clonal expansion, RNA sequencing, manipulation within enclosed systems, controlling cell-cell interactions, and isolating precious microtissues from heterogeneous mixtures. We propose that the optoelectronic microrobotic system, which can be implemented using a microscope and consumer-grade optical projector, will be useful for a wide range of applications in the life sciences and beyond.

It is known that CH3NH3PbI3 perovskite films with high crystallization and controlled morphology always show enhanced power conversion efficiency. Here we incorporate a small amount of polyvinylidene fluoride–trifluoroethylene polymer P(VDF-TrFE) into PbI2 solution to control the crystallinity and morphology of perovskite layer in a two-step deposition process. Our results show that the P(VDF-TrFE) bridges the grain boundaries and also enhances the crystallinity of the perovskite layer significantly. By adjusting P(VDF-TrFE) concentration, the fabricated perovskite solar cells show improved average power conversion efficiency from 9.57 ± 0.25% to 12.54 ± 0.40% under a standard illumination of 100 milliwatts per square centimeter, which increases by nearly 31%. Thus, we demonstrate a new strategy to control the crystallinity and morphology of perovskite films by incorporating polymer into PbI2 film in a two-step deposition process. In addition, this method has been proven as an effective way to prepare high-performance perovskite solar cells.

Poly(vinyl pyrrolidone) (PVP)-based carbon/Fe3C composite nanofibers (C/Fe3C CNFs) have been successfully prepared by carbonization of as-electrospun PVP/ferric nitrate nanofibers. Unlike the pristine PVP nanofibers, the PVP/ferric nitrate nanofibers can retain fibers structure after carbonization, in which Fe3C nanoparticles are well-dispersed. More importantly, the as-prepared wax composites exhibit high electromagnetic wave absorption abilities, which can be attributed to the formation of the C/Fe3C CNFs “conductive network”, and leads to a more effective dielectric loss in terms of dissipating the induced current in the wax composites. Specifically, the CNFs/wax composites with a low filler ratio of 10 wt% shows the minimum reflection loss of −62.6 dB at 11.25 GHz in a thin matching thickness of 3.6 mm, and the effective bandwidth below −10 dB can reach up to 6.5 GHz. Thus, this work demonstrates a facile, cost-effective synthesized strategy to prepare carbon-based lightweight composite nanofibers with superior electromagnetic wave absorption properties.

Over the past forty years, anammox-based processes have been extensively researched and applied to some extent. However, some of the long-standing problems present serious impediments to wide application of these processes, and knowledge gap between lab-scale research and full-scale operations is still considerable. In recent years, anammox-based research has developed rapidly and some emerging concepts have been proposed. The focus of this review is on the critical problems facing actual application of anammox processes. The latest developments in anammox-based processes are summarized, and particular consideration is given to the following aspects: (1) the evolution of the chemical stoichiometry of anammox reaction; (2) the status of several main anammox-based processes; (3) the critical problems and countermeasures; (4) the emerging anammox-based processes; and (5) the suggested optimal process integrating partial nitritation, anammox, hydroxyapatite crystallization and denitratation for digestion effluent treatment towards more efficient nitrogen removal and phosphorus recovery in the future.

Abstract Developing pseudocapacitive materials for electrochemical energy storage generally relies on the formation of nanosize and/or nanoporous particles with short solid‐state diffusion distance and high surface area, which leads to low volumetric capacity and severe parasitic reactions. In this work, nonporous bulky heterogeneous particles composed of TiO 2 matrix and phosphorus are reported for high volumetric pseudocapacitive Na storage. An in situ formed 3D titanium phosphate interphase serves as a fast ionic transport network, allowing rapid sodiation/desodiation processes within the particles. Such nonporous heterogeneous particles exhibit “interface‐induced pseudocapacitance” with an enhanced volumetric capacity, which is over 50% higher than that of commercial hard carbon anodes. This study demonstrates heterogeneous particles with a well‐engineered nanostructure as a new paradigm for electrode materials design.

The amyloid beta (Aβ) fibrillar aggregate is the hallmark of Alzheimer’s disease (AD). Disassembling preformed fibril or inhibiting Aβ aggregation is considered as a therapeutic strategy for AD. Increasing evidence shows that green tea extracts, epigallocatechin-3-gallate (EGCG, containing an extra gallic acid ester group compared to EGC) and epigallocatechin (EGC), can disassociate Aβ fibrils and attenuate Aβ toxicity. However, the underlying molecular mechanism is poorly understood. Herein, we performed microsecond all-atom molecular dynamics (MD) simulations to investigate the influences of EGCG/EGC on the newly cryo-EM resolved LS-shaped Aβ42 protofibrils and their detailed interactions. MD simulations demonstrate that both EGCG and EGC can disrupt Aβ42 protofibril and EGCG displays a higher disruptive capacity than EGC. EGCG alters the L-shape of Aβ42 protofibril by breaking the hydrogen bond between H6 and E11 through π–π interactions with residues H14/Y10 and hydrogen-bonding interactions with E11, while EGC remodels the L-shape by inserting into the hydrophobic core formed by A2, F4, L34, and V36 and via aromatics interaction with H6/Y10. EGCG disrupts the salt bridges between the K28 side chain and A42 COO– through hydrogen-bonding interaction with A42 and cation−π interaction between its gallic acid ester group and K28, while EGC damages the salt bridges through hydrophobic interactions with V39 and I41 as well as with I32, M35, and V40 located in the C-terminal hydrophobic core. This study demonstrates the pivotal role of the gallic acid ester group of EGCG in disrupting Aβ42 protofibril and provides atomic-level insights into the distinct mechanism by which EGCG and EGC disrupt Aβ protofibril, which could be useful for designing amyloid inhibitors.

Mo-doped nickel-rich LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode material is prepared by a solid-state method to enhance the high voltage electrochemical performances of the NCM622 material for lithium-ion batteries. The molybdenum element is proved to be homogeneously distributed inside the particles of the NCM622 material according to the result from the EDS mapping of the particle cross-section. The effects of Mo doping on the crystal structure, morphology, electrochemical properties and high-temperature performances of the NCM622 material are investigated in detail. The Mo-doped sample delivers a discharge capacity of 203.1 mAh/g and a capacity retention of 82.96% after 100 cycles at 1C under a high cut-off voltage of 4.6 V. Besides, the Mo-modified material exhibits a better rate performance of 159.9 mAh/g at 8C and lower voltage fading compared with the unmodified material. The significant improvements in electrochemical properties are ascribed to the fact that trace Mo ions doped into the transition-metal layer help to enlarge the lithium slab spacing, stabilize the crystal structure and suppress the electrode polarization. It is also demonstrated that Mo doping effectively suppresses the pulverization of particles and reduces the charge transfer resistance according to the SEM and EIS analyses.

Confronted with microwave pollution issues, there is an urgent need for microwave absorption materials that possess optimal combinations of dielectric loss and magnetic loss properties. While a variety of studies focus on the components, the construction of nanostructure is rarely studied, which is of equivalent significance to microwave absorber design. In this work, Co-ZIF-67 was adopted as self-template to grow N-doped graphene/carbon nanotube interlinked conductive networks in-situ under a one-step carbonization process with tailored microwave absorption properties. Diverse microwave absorption performance could be achieved by directly adjusting the proportions among ingredients and the calcination temperature, obtaining a maximum value of reflection loss of −65.45 dB at 17.5 GHz with a sample thickness of just 1.5 mm. The effective absorption bandwidth could be tailored from 3.75 to 18 GHz among different thickness as required. The nanostructures had an apparent impact on the corresponding microwave absorption performance, in which the N-doped carbon-based conductive networks, ferromagnetic cobalt atoms, and interfaces among heterostructure strengthened the dipolar polarization and conductivity loss, magnetic loss, and interfacial polarization, respectively. This synthesis strategy offers a promising pathway for integrating nanostructures and functions, catering to requirements for designing and optimizing prospective microwave absorbers.

In this article, a three-dimensional chemically reduced graphene oxide/polypyrrole nanotubes (PPy nanotubes)/Fe3O4 aerogel (GPFA) was fabricated by a simple one-step self-assembly process through hydrothermal reduction. The addition of both PPy nanotubes and Fe3O4 nanoparticles is aimed to avoid the aggregation of graphene sheets, effectively adjust the permittivity, and make better impedance matching between dielectric loss and magnetic loss of the composite aerogel to gain excellent electromagnetic (EM) wave absorption performance. The EM wave-absorbing results indicate that the ternary composite with an ultralow density of about 38.3 mg/cm3 shows an improved EM wave-absorbing property with a maximum reflection loss of -49.2 dB at the frequency of 11.8 GHz, with an effective absorption bandwidth below -10 dB reaching 6.1 GHz (9.8-15.9 GHz) at a thickness of 3.0 mm. Such an outstanding EM wave absorption behavior can be attributed to the multiple reflections, polarizations, and relaxation processes in the aerogel.

High-dimensional entanglement has demonstrated its potential for increasing channel capacity and resistance to noise in quantum information processing. However, distributing it is a challenging task, imposing severe restrictions on its application. Here we report the first distribution of three-dimensional orbital angular momentum (OAM) entanglement via a 1-km-long few-mode optical fiber. Using an actively stabilizing phase precompensation technique, we successfully transport one photon of a three-dimensional OAM entangled photon pair through the fiber. The distributed OAM entangled state still shows a fidelity up to 71% with respect to the three-dimensional maximally entangled state (MES). In addition, we certify that the high-dimensional quantum entanglement survives the transportation by violating a generalized Bell inequality, obtaining a violation of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo>∼<!-- ∼ --></mml:mo> <mml:mn>3</mml:mn> </mml:math> standard deviations from the classical limit with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msub> <mml:mi>I</mml:mi> <mml:mn>3</mml:mn> </mml:msub> </mml:mrow> <mml:mo>=</mml:mo> <mml:mn>2.12</mml:mn> <mml:mo>±<!-- ± --></mml:mo> <mml:mn>0.04</mml:mn> </mml:math> . The method we developed can be extended to a higher OAM dimension and larger distances in principle. Our results make a significant step towards future OAM-based high-dimensional long-distance quantum communication.

The classical heterogeneous nucleation theory explains that the groove in the substrate is a desirable place to breed a bubble nucleus. However, the existing research method cannot reproduce the nucleation process. Therefore, in the present study, the molecular dynamics simulation method is conducted to investigate the bubble nucleation on grooved substrates with different wettability. The simple L-J liquid argon is heated by the platinum grooved substrate, whose temperature is controlled by Langevin thermostat. Results show that the groove has significant impacts on bubble nucleation from two aspects: improve thermal energy transfer efficiency and support an initial bubble nucleus. For the substrate with a hydrophilic groove, a visible bubble nucleus generates on the groove region from nothing because of liquid in there obtaining more thermal energy than that on the smooth region within the same time. Moreover, the nucleation rate is improved with the increase of groove hydrophilicity. On the other hand, for the substrate with a hydrophobic groove, some residual gases form an initial bubble nucleus at the initial moment of the nonequilibrium simulation stage, and it takes some time to grow up. Furthermore, a method based on the competition between atomic potential energy and atomic kinetic energy is used to explain the formation of the bubble nucleus on the different wetting substrates. The present simulation study of bubble nucleation on the grooved substrate is another support for the classical heterogeneous nucleation theory.

Although flaviviruses co-opt the function of the host endoplasmic reticulum (ER) membrane protein complex (EMC) during infection, a mechanistic explanation for this observation remains unclear. Here, we show that the EMC promotes biogenesis of dengue virus (DENV) and Zika virus (ZIKV) non-structural multi-pass transmembrane proteins NS4A and NS4B, which are necessary for viral replication. The EMC binds to NS4B and colocalizes with the DENV replication organelle. Mapping analysis reveals that the two N-terminal marginally hydrophobic domains of NS4B confer EMC dependency. Furthermore, altering the hydrophobicity of these two marginally hydrophobic domains relieves NS4B’s EMC dependency. We demonstrate that NS4B biogenesis, but not its stability, is reduced in EMC-depleted cells. Our data suggest that the EMC acts as a multi-pass transmembrane chaperone required for expression of at least two virally encoded proteins essential for flavivirus infection and point to a shared vulnerability during the viral life cycle that could be exploited for antiviral therapy.

Abstract Atomically thin oxychalcogenides have been attracting intensive attention for their fascinating fundamental properties and application prospects. Bi 2 O 2 Se, a representative of layered oxychalcogenides, has emerged as an air‐stable high‐mobility 2D semiconductor that holds great promise for next‐generation electronics. The preparation and device fabrication of high‐quality Bi 2 O 2 Se crystals down to a few atomic layers remains a great challenge at present. Here, molecular beam epitaxy (MBE) of atomically thin Bi 2 O 2 Se films down to monolayer on SrTiO 3 (001) substrate is achieved by co‐evaporating Bi and Se precursors in oxygen atmosphere. The interfacial atomic arrangements of MBE‐grown Bi 2 O 2 Se/SrTiO 3 are unambiguously revealed, showing an atomically sharp interface and atom‐to‐atom alignment. Importantly, the electronic band structures of one‐unit‐cell (1‐UC) thick Bi 2 O 2 Se films are observed by angle‐resolved photoemission spectroscopy (ARPES), showing low effective mass of ≈0.15 m 0 and bandgap of ≈0.8 eV. These results may be constructive to the synthesis of other 2D oxychalcogenides and investigation of novel physical properties.

Background Asthenoteratospermia, one of the most common causes for male infertility, often presents with defective sperm heads and/or flagella. Multiple morphological abnormalities of the sperm flagella (MMAF) is one of the common clinical manifestations of asthenoteratospermia. Variants in several genes including DNAH1 , CEP135 , CATSPER2 and SUN5 are involved in the genetic pathogenesis of asthenoteratospermia. However, more than half of the asthenoteratospermia cases cannot be explained by the known pathogenic genes. Methods and results Two asthenoteratospermia-affected men with severe MMAF (absent flagella in &gt;90% spermatozoa) from consanguineous families were subjected to whole-exome sequencing. The first proband had a homozygous missense mutation c.188G&gt;A (p.Arg63Gln) of DZIP1 and the second proband had a homozygous stop-gain mutation c.690T&gt;G (p.Tyr230*). Both of the mutations were neither detected in the human population genome data (1000 Genomes Project, Exome Aggregation Consortium) nor in our own data of a cohort of 875 Han Chinese control populations. DZIP1 encodes a DAZ (a protein deleted in azoospermia) interacting protein, which was associated with centrosomes in mammalian cells. Immunofluorescence staining of the centriolar protein Centrin1 indicated that the spermatozoa of the proband presented with abnormal centrosomes, including no concentrated centriolar dot or more than two centriolar dots. HEK293T cells transfected with two DZIP1 -mutated constructs showed reduced DZIP1 level or truncated DZIP1. The Dzip1 -knockout mice, generated by the CRSIPR-Cas9, revealed consistent phenotypes of severe MMAF. Conclusion Our study strongly suggests that homozygous DZIP1 mutations can induce asthenoteratospermia with severe MMAF. The deficiency of DZIP1 induces sperm centrioles dysfunction and causes the absence of flagella.

In low-strength ammonium wastewater (LSAWW) treatment, the application of anammox-based process is still limited due to extreme instability and the poor nitrogen removal rate (NRR). In this work, granule sludge, comprised of functional microbes and hydroxyapatite (HAP), was inoculated and cultivated in a one-stage partial nitritation/anammox (PNA) reactor for LSAWW treatment. The results showed that at the hydraulic retention time (HRT) of about 1.0 h and the influent ammonium concentration of 63.0 mg/L, an average NRR of 1.28 kg/m3/d was achieved, which far exceeds that reported in similar studies. The main inorganic matter in sludge was identified as HAP through the X-ray diffractometer and Raman spectrum analysis. The tomographic images of wet granule created through computed tomography revealed that the interior density of the granules was uneven and many hollow structures existed in the granule interior. Combined with the Scanning Electron Microscope images of dry granules, it was found that the granules were comprised of hollow sub-granules. Since the biomass in the reactor increased with no obvious increase in the granule size, it was inferred that the hollow sub-granules had fragile connections with each other and that granules division occurred easily, resulting in the high dispersity of sludge. Florescence in situ hybridization results also showed that the ammonium-oxidizing bacteria and anammox bacteria were mainly distributed in the two sides of the sub-granule shells and the HAP in the middle. This kind of structure raised the density of granules and improved the settleability of sludge, which made it possible to achieve a high biomass in the reactor at a short HRT. Therefore, the sludge formed in the reactor was concentrated, highly dispersive and easily settleable. These factors appear to be crucial for achieving the desired nitrogen removal performance. This study marks a big leap in LSAWW treatment through the one-stage PNA process and has great potential in actual applications.

Mechanical energy such as the wind flow widely exists in nature as renewable and sustainable energy source. It could be converted into electrical energy throughout piezoelectricity which has capability for converting mechanical energy into electrical energy. In this paper, an innovation piezoelectric energy harvesting (PEH) system is proposed by using the piezoelectric macro fiber composites (MFC) based on flutter mode. It is demonstrated that this PEH-MFC system exhibits the excellent characteristic of flexibility on large deformation and reliability in energy harvesters and effectively captures power from wind energy. The PEH-MFC system is composed of a soft substrate linked with a polymer triangular leaf by a copper hinge. The active MFC is attached at the bottom of the soft substrate as the core component of system. A series of experiments on energy harvesting systems for various substrate materials and various types of MFC are performed in wind tunnel. The flutter mode is obtained under the critical flutter wind speed in order to acquire the excellent behavior of extracting power through this innovation PEH-MFC system. The experimental results show that the thickness and stiffness of PEH substrate have significant effects on the performance of energy harvesting. The maximum peak-to-peak open circuit voltage of 82 V is obtained using the MFC-2807 with Al substrate at the wind speed of 7.5 m/s. The resulting direct voltage and electric power are 25.8 V and 0.54 mW with a load resistance of 680 kΩ, respectively. It is concluded that the proposed energy harvesting system using MFC based on flutter mode can generate a power efficiency of 9.18 mW/cm3 which can meet the requirement of conventional MEMS.

Abstract There is great interest in the development of micromotors which can convert energy to motion in sub-millimeter dimensions. Micromachines take the micromotor concept a step further, comprising complex systems in which multiple components work in concert to effectively realize complex mechanical tasks. Here we introduce light-driven micromotors and micromachines that rely on optoelectronic tweezers (OET). Using a circular micro-gear as a unit component, we demonstrate a range of new functionalities, including a touchless micro-feed-roller that allows the programming of precise three-dimensional particle trajectories, multi-component micro-gear trains that serve as torque- or velocity-amplifiers, and micro-rack-and-pinion systems that serve as microfluidic valves. These sophisticated systems suggest great potential for complex micromachines in the future, for application in microrobotics, micromanipulation, microfluidics, and beyond.

The emergence of multi-principal element alloys (MPEAs) holds great promise for the development of high performance metallic materials. However, it remains unclear whether MPEAs can provide previously unknown deformation mechanisms to drastically enhance their mechanical performance. Here we report a new deformation mechanism of mechanically-induced dual phase transformations from the face-centered cubic (FCC) to hexagonal close- packed (HCP) phase and then back to the FCC phase with nanotwins in a CrCoNi medium-entropy alloy (MEA). During the two sequential steps of phase transformation, continued shear occurs in the same 〈110〉FCC∥〈112¯0〉HCPdirection along different {111}FCC∥(0001)HCP planes, producing a total shear transformation strain up to 70%. The dual phase transformations stem from a unique capability of facile slip in between the close-packed {111}FCC∥(0001)HCP atomic layers in both FCC and HCP phases, leading to flexible stacking sequences of those close-packed layers with low stacking fault energies. Our work demonstrates that MPEAs can offer unconventional deformation mechanisms such as dual phase transformations in the CrCoNi MEA, thereby opening opportunities for enhancing the mechanical properties of advanced alloys.

Solid solution strengthening is one of the most conventional strategies for optimizing alloys strength, while the corresponding mechanisms can be more complicated than we traditionally thought specifically as heterogeneity of microstructure is involved. In this work, by comparing the change of chemical distribution, dislocation behaviors and mechanical properties after doping equivalent amount of tungsten (W) atoms in CrCoNi alloy and pure Ni, respectively, it is found that the alloying element W in CrCoNi alloy resulted in much stronger strengthening effect due to the significant increase of heterogeneity in chemical distribution after doping trace amount of W. The large atomic scale concentration fluctuation of all elements in CrCoNi-3W causes dislocation motion via strong nanoscale segment detrapping and severe dislocation pile up which is not the case in Ni-3W. The results revealed the high sensitivity of elements distribution in multi-principle element alloys to composition and the significant consequent influence in tuning the mechanical properties, giving insight for complex alloy design.

In the field of bionic soft robots and microrobots, artificial muscle materials have exhibited unique potential for cutting-edge applications. However, current mainstream thermal-responsive artificial muscles based on semicrystalline polymers (SCPs), despite their excellent physical properties, suffer from the limitation of environmental stimuli in practice, while their photodriven counterparts adopting liquid crystal elastomers (LCEs) lack ductility. Herein, a novel multifunctional programmable artificial muscle with a unique patch-sewing structure formed by π–π stacking between azobenzene groups was designed, which combined the advantages of SCPs and LCEs. The nanocomposite demonstrated a unique combination between artificial muscle performance (46.5 times the energy density and 26.6 times the power density of human skeletal muscles) and programmability (274.84% strain and 100% shape-memory recovery rate within 1 s). Meanwhile, coupling the photoisomerization of azobenzene and the photothermal conversion of gold nanorods, the cycle of deformation triggered by ultraviolet light and restoring by infrared light could be accomplished rapidly within 30 s. A COMSOL Multiphysics model was established and the corresponding finite element analysis verified the photoactuation and captured the general principle of light initiation in elastomers. These demonstrate that the multifunctional programmable elastomer is promising for artificial muscle applications, especially for photoinduced actuation.

To achieve optimal functional recovery of articular cartilage, scaffolds with nanofibrous structure and biological function have been widely pursued. In this study, two-dimensional electrospun poly(l-lactide-co-ε-caprolactone)/silk fibroin (PLCL/SF) scaffolds (2DS) were fabricated by dynamic liquid support (DLS) electrospinning system, and then cross-linked with hyaluronic acid (HA) to further mimic the microarchitecture of native cartilage. Subsequently, three-dimensional PLCL/SF scaffolds (3DS) and HA-crosslinked three-dimensional scaffolds (3DHAS) were successfully fabricated by in situ gas foaming and freeze-drying. 3DHAS exhibited better mechanical properties than that of the 3DS. Moreover, all scaffolds exhibited excellent biocompatibility in vitro. 3DHAS showed better proliferation and phenotypic maintenance of chondrocytes as compared to the other scaffolds. Histological analysis of cell-scaffold constructs explanted 8 weeks after implantation demonstrated that both 3DS and 3DHAS scaffolds formed cartilage-like tissues, and the cartilage lacuna formed in 3DHAS scaffolds was more mature. Moreover, the reparative capacity of scaffolds was discerned after implantation in the full-thickness articular cartilage model in rabbits for up to 12 weeks. The macroscopic and histological results exhibited typical cartilage-like character and well-integrated boundary between 3DHAS scaffolds and the host tissues. Collectively, biomimetic 3DHAS scaffolds may be promising candidates for cartilage tissue regeneration applications.

A 20 L hollow-fiber submerged anaerobic membrane bioreactor (SAnMBR) was used to treat real domestic wastewater at 25 °C with hydraulic retention times (HRTs) ranging from 4 to 12 h. The process performance was evaluated by organic removal efficiency, biogas production, sludge yield, and filtration behaviors during one-year's operation. For HRTs ranging between 6 and 12 h, the AnMBR showed good organic removal efficiency with chemical oxygen demand (COD) and biochemical oxygen demand (BOD) removal efficiencies of about 89% and 93%, respectively. The biogas yield was 0.26 L-gas/g-CODfed, with approximately 80% methane content, and the sludge yield was 0.07–0.11 g-VSS/g-CODrem. While at an HRT of 4 h, with the higher wastewater treatment capacity and organic loading rate (OLR), the biogas production was lower (0.17 L-gas/g-CODfed), and the sludge production was higher (0.22 g-VSS/g-CODrem). The organic removal performance (COD 84% and BOD 89%) at HRT of 4 h was acceptable due to the effective separation effect of the membrane filtration process. According to COD balance analysis, the low biogas yield and high sludge yield at HRT of 4 h were due to insufficient biodegradation under an OLR of 2.05 g-COD/L-reactor/d. Theoretical calculations based on Henry's law indicate that the ideal methane content in the biogas should be 82–85% when the operational temperature was 25 °C. To achieve a high flux and sustainable AnMBR operation, the impact of mixed liquor suspended solid (MLSS) and gas sparging velocity (GSV) on the filtration performance was analyzed. The critical flux increased with increase in the GSV from 24.2 to 174.3 m/h, but decreased with increase in the MLSS concentration from 8.2 to 20.2 g/L. Therefore, decreasing fouling rate to 0.8–1.2 kPa/d by efficiently controlling GSV and MLSS, sustainable operation could be achieved at a flux of 0.34 m/d.

Electrospun nanofibers emulate extracellular matrix (ECM) morphology and architecture; however, small pore size and tightly-packed fibers impede their translation in tissue engineering. Here we exploited in situ gas foaming to afford three-dimensional (3D) poly(L-lactide-co-ε-caprolactone)/silk fibroin (PLCL/SF) scaffolds, which exhibited nanotopographic cues and a multilayered structure. The addition of SF improved the hydrophilicity and biocompatibility of 3D PLCL scaffolds. Three-dimensional scaffolds exhibited larger pore size (38.75 ± 9.78 μm2) and high porosity (87.1% ± 1.5%) than that of their 2D counterparts. 3D scaffolds also improved the deposition of ECM components and neo-vessel regeneration as well as exhibited more numbers of CD163+/CCR7+ cells after 2 weeks implantation in a subcutaneous model. Collectively, 3D PLCL/SF scaffolds have broad implications for regenerative medicine and tissue engineering applications.

A submerged anaerobic membrane bioreactor (SAnMBR) was used in the treatment of real municipal wastewater at operation temperatures ranging from 15 °C to 25 °C and hydraulic retention time (HRT) of 6 h. The treatment process was evaluated in terms of organic removal efficiency, biogas production, sludge growth and membrane filtration. During long-term operation, the SAnMBR achieved chemical oxygen demand removal efficiencies of about 90% with a low sludge yield (0.12–0.19 g-VSS/g-CODrem) at 20–25 °C. Approximately 1.82–2.27 kWh/d of electric energy was generated during the wastewater treatment process at 20–25 °C, 0.67 kWh/d was generated at 15 °C. The microbial community analysis results showed that microbial community was dominated by aceticlastic methanogens, coupled by hydrogenotrophic methanogens and a very small quantity of methylotrophic methanogens. It was also shown that the stabilization of the microbial community could be attributed to the carbohydrate-protein degrading bacteria and the carbohydrate degrading bacteria.

Intracerebral hemorrhage (ICH) is a destructive form of stroke that often results in death or disability. However, the survivors usually experience sequelae of neurological impairments and psychiatric disorders, which affect their daily functionality and working capacity. The recent MISTIE III and STICH II trials have confirmed that early surgical clearance of hematomas does not improve the prognosis of survivors of ICH, so it is vital to find the intervention target of secondary brain injury (SBI) after ICH. Mitochondrial dysfunction, which may be induced by oxidative stress, neuroinflammation, and autophagy, among others, is considered to be a novel pathological mechanism of ICH. Moreover, mitochondria play an important role in promoting neuronal survival and improving neurological function after a hemorrhagic stroke. This review summarizes the mitochondrial mechanism involved in cell death, reactive oxygen species (ROS) production, inflammatory activation, blood–brain barrier (BBB) disruption, and brain edema underlying ICH. We emphasize the potential of mitochondrial protection as a potential therapeutic target for SBI after stroke and provide valuable insight into clinical strategies.

Abstract EGFR-targeted chimeric antigen receptor (CAR) T cells are potent and specific in suppressing the growth of triple-negative breast cancer (TNBC) in vitro and in vivo. However, in this study, a subset of mice soon acquired resistance, which limits the potential use of EGFR CAR T cells. We aimed to find a way to overcome the observed resistance. Transcriptomic analysis results revealed that EGFR CAR T-cell treatment induced a set of immunosuppressive genes, presumably through IFNγ signaling, in EGFR CAR T-cell–resistant TNBC tumors. The EGFR CAR T-cell–induced immunosuppressive genes were associated with EGFR CAR T-cell–activated enhancers and were especially sensitive to THZ1, a CDK7 inhibitor we screened out of a panel of small molecules targeting epigenetic modulators. Accordingly, combination therapy with THZ1 and EGFR CAR T cells suppressed immune resistance, tumor growth, and metastasis in TNBC tumor models, including human MDA-MB-231 cell–derived and TNBC patient–derived xenografts, and mouse EMT6 cell–derived allografts. Taken together, we demonstrated that transcriptional modulation using epigenetic inhibitors could overcome CAR T-cell therapy–induced immune resistance, thus providing a therapeutic avenue for treating TNBC in the clinic.

Reactive oxygen species (ROS), acting as essential mediators in biological system, play important roles in the physiologic and pathologic processes, including cellular signal transductions and cell homeostasis interference. Aberrant expression of ROS in tissue microenvironment can be caused by the internal/external stimuli and tissue injury, which may leads to an elevated level of oxidative stress, inflammatory response, and cellular damage as well as disruption in the tissue repair process. To prevent the formation of excess ROS around the injury site, advanced biomaterials can be remodeled or instructed to release their payloads in an injury microenvironment-responsive fashion to regulate the elevated levels of the ROS, which may also help downregulate the oxidative stress and promote tissue regeneration. A multitude of scaffolds and bioactive cues have been reported to promote the regeneration of damaged tissues based on the scavenging of free radicals and reactive species that confer high protection to the cellular activity and tissue function. In this review, we outline the underlying mechanism of ROS generation in the tissue microenvironment and present a comprehensive review of ROS-scavenging biomaterials for regenerative medicine and tissue engineering applications, including soft tissues regeneration, bone and cartilage repair as well as wound healing. Additionally, we highlight the strategies for the regulation of ROS by scaffold design and processing technology. Taken together, developing ROS-based biomaterials may not only help develop advanced platforms for improving injury microenvironment but also accelerate tissue regeneration.

Functional segmental trachea reconstruction remains a remarkable challenge in the clinic. To date, functional trachea regeneration with alternant cartilage-fibrous tissue-mimetic structure similar to that of the native trachea relying on the three-dimensional (3D) bioprinting technology has seen very limited breakthrough. This fact is mostly due to the lack of tissue-specific bioinks suitable for both cartilage and vascularized fibrous tissue regeneration, as well as the need for firm interfacial integration between stiff and soft tissues. Here, a novel strategy is developed for 3D bioprinting of cartilage-vascularized fibrous tissue-integrated trachea (CVFIT), utilizing photocrosslinkable tissue-specific bioinks. Both cartilage- and fibrous tissue-specific bioinks created by this study provide suitable printability, favorable biocompatibility, and biomimetic microenvironments for chondrogenesis and vascularized fibrogenesis based on the multicomponent synergistic effect through the hybrid photoinitiated polymerization reaction. As such, the tubular analogs are successfully bioprinted and the ring-to-ring alternant structure is tightly integrated by the enhancement of interfacial bonding through the amidation reaction. The results from both the trachea regeneration and the in situ trachea reconstruction demonstrate the satisfactory tissue-specific regeneration along with realization of mechanical and physiological functions. This study thus illustrates the 3D-bioprinted native tissue-like trachea as a promising alternative for clinical trachea reconstruction.

Transition metal sulfides (TMSs) have become promising candidates as electrode materials in energy storage fields thanks to the high theoretical capacity. However, their application is hindered by depressed electrical conductivity and poor cycling performance. Herein, we proposed a ZIF-67 derived, nitrogen-doped, graphene-coated and carbon nanotubes-interlinked 3D Co3S4/C conductive network (N–Co3S4-GN/CNT) for high-performance supercapacitors. Through controlling the mass ratio of ZIF-67, melamine and g-C3N4, various microstructures with determined electrochemical performance could be achieved. The nanocomposites synthesized with the ingredient mass ratio of 2: 1: 1 (NCSC-211) were proven to have the most excellent comprehensive electrochemical properties. In the NCSC-211 nanostructure, multi-layer graphene function as conductive shells for improved cycling performance by alleviating pulverization caused by volume change, thick CNTs act as conductive bridges and agglomeration spacers that increase electron conductivity and provide more active sites for redox reaction and doped-nitrogen offer enhanced wettability to electrolyte and faster electron transfer. The NCSC-211 electrode displayed specific capacitance of 1158 F g−1 at 1 A g−1, rate capability of 86% at 10 A g−1 and extraordinary cycling stability with 97.2% capacitive retention after 4000 cycles. Furthermore, the assembled asymmetric supercapacitor NCSC-211//activated carbon exhibited energy density of 43.73/37.69 Wh kg−1 at power density of 800/8000 W kg−1 and capacity retention of 95.3% after 5000 cycles at 5 A g−1. The designing strategy of in-situ grown instead of additional added conductive phase that fully-covered and strongly-interlinked network nanostructure may pave the road towards TMSs in synthesizing energy storage materials by compensating their intrinsic drawbacks.

Super-hard and corrosion-resistant (AlCrMoSiTi)Nx high-entropy nitride coatings were prepared using a novel multi-arc cathodic vacuum magnetic filtration deposition at different N2 gas flow rates (RN) of 0, 20, 50 and 70 sccm. The influence of RN on the element composition, phase structure, mechanical, tribological and corrosion properties of the coatings were systematically studied. Higher RN promoted higher N contents in the coatings that resulted in a transformation from an amorphous to face-centered-cubic (FCC) phase. At a high N content of 49 at. % (RN = 70%), the coating exhibits a simple FCC structure, and offers a superior combination of super-hardness, excellent wear and corrosion resistance. The exceptional hardness of the (AlCrMoSiTi)N coating (41.6 GPa) that surpasses most high-entropy ceramics is underlain by the formation of strong metal-nitride phase, the solid-solution strengthening and the fine grain strengthening. Therefore, (AlCrMoSiTi)Nx nitride coating presents a potential application in protective coating owing to its extraordinary mechanical properties and corrosion resistance.

The anaerobic ammonia oxidation (anammox) process is a promising biological nitrogen removal technology. However, owing to the sensitivity and slow cell growth of anammox bacteria, long startup time and initially low nitrogen removal rate (NRR) are still limiting factors of practical applications of anammox process. Moreover, nitrogen removal efficiency (NRE) is often lower than 88 %. This review summarizes the most common methods for improving NRR by increasing microorganism concentration, and modifying reactor configuration. Recent integrated anammox-based systems were evaluated, including hydroxyapatite (HAP)-enhanced one-stage partial nitritation/anammox (PNA) process for a high NRR of over 2 kg N/m3/d at 25 °C, partial denitrification/anammox (PDA) process, and simultaneous partial nitrification, anammox, and denitrification process for a high NRE of up to 100 %. After discussing the challenges for the application of these systems critically, a combined system of anaerobic digestion, HAP-enhanced one-stage PNA and PDA is proposed in order to achieve a high NRR, high NRE, and phosphorus removal simultaneously.

Sustained-release drug-loaded microspheres provide a long-acting sustained release, with targeted and other effects. There are many types of sustained-release drug microspheres and various preparation methods, and they are easy to operate. For these reasons, they have attracted widespread interest and are widely used in tissue engineering and other fields. In this paper, we provide a systematic review of the application of sustained-release drug microspheres in tissue engineering. First, we introduce this new type of drug delivery system (sustained-release drug carriers), describe the types of sustained-release drug microspheres, and summarize the characteristics of different microspheres. Second, we summarize the preparation methods of sustained-release drug microspheres and summarize the materials required for preparing microspheres. Third, various applications of sustained-release drug microspheres in tissue engineering are summarized. Finally, we summarize the shortcomings and discuss future prospects in the development of sustained-release drug microspheres. The purpose of this paper was to provide a further systematic understanding of the application of sustained-release drug microspheres in tissue engineering for the personnel engaged in related fields and to provide inspiration and new ideas for studies in related fields.

The electromagnetic wave irradiation has obstructed the precise operation of the high-tech electronic equipment and threatened the health of the bodies during the 5G era. It is critical to develop electromagnetic interference (EMI) shielding materials with remarkable shielding effectiveness along with lightweight and flexible properties, while the integrations of the heat management performances have been gradually indispensable, especially in wearable electronic device applications. Anchoring the Ti3C2Tx MXene nanosheets on the surfaces of the recycled carbon fibers (RCF) and assembling heterostructure can be regarded as effective strategies, while simultaneously solving the conductivity reduction and the corresponding performance degradation bottlenecks of the thermal-recycling carbon fiber. The construction of the RCF-MXene paper performs remarkable EMI shielding performance of 45.7 dB, while the specific SE/t can be improved to 7723.85 dB cm2 g-1, along with impressive photothermal and electrothermal conversion abilities. After coating PDMS layers, the flexible [email protected] film maintains stable EMI shielding performance when experiencing in-situ electrothermal conversion and after 10000-cycle mechanical deformation processes. Exhibiting multifunctionality by facile synthesis strategies, the RCF-MXene-based materials provide great potential as next-generation candidates in wearable electronic devices, together with promoting the advancement of the sustainable reuse of the carbon fibers resources.

High-entropy nitride coatings have become a promising alternative to traditional protective coatings due to their excellent mechanical properties, thermal stability, oxidation, and wear resistance. However, the design and fabrication of hard high-entropy nitride coatings remain a great challenge. In this study, (MoSiTiVZr)Nx high-entropy nitride coatings were deposited by reactive DC magnetron sputtering at different nitrogen flow. The chemical compositions, structures, hardness, damage-tolerance, friction and corrosion resistances of the coatings were investigated. With the increase of nitrogen content in the coatings, the phase structure transforms from an amorphous structure to a single face centered cubic structure, and all alloying elements form metal-nitrogen bonds. The coating with nitrogen content of 53.7 at% exhibits an ultrahigh hardness of 45.6 GPa and the best damage-tolerance and wear resistance. The coatings with low nitrogen contents show better corrosion resistance than 304 stainless steels, however, an increase in nitrogen content results in a slight decrease in corrosion resistance. The mechanism of the structures, mechanical properties and corrosion resistance of (MoSiTiVZr)Nx coatings are discussed in details.

Transparent wood (TW) has been developed to combine the optical and functional aspects of wood. Many efforts have been dedicated to adding quantum dots, nanoparticles, or dyes to TW to provide additional functionalities, such as luminescent, electrochromic, thermochromic, and photo-switchable TW. However, the UV shielding performance and its new application of transparent wood are needed to explore. Herein, we report a photochromic transparent wood (PTW) by incorporating poly(methyl methacrylate) and UV/visible light switchable molecules into the delignified wood template. The focus is to investigate the relationship of process-structure-property of the PTW. The dispersion of photochromic molecules in PTW is shown by using energy-dispersive X-ray spectroscopy. The transmittance and the color of the PTW are switchable under UV and visible light excitation due to a change from the closed-ring to the open-ring form. Moreover, the PTW was found to possess, UV shielding performance, favorable thermal and mechanical properties, as well as excellent dimensional stability. We also demonstrate the potential smart packaging application of the UV-blocking PTW. We envision this PTW could be utilized for anti-counterfeit materials, intelligent sensors, and smart indicators.

Three principal ER quality-control mechanisms, namely, the unfolded protein response, ER-associated degradation (ERAD), and ER-phagy are each important for the maintenance of ER homeostasis, yet how they are integrated to regulate ER homeostasis and organellar architecture in vivo is largely unclear. Here we report intricate crosstalk among the 3 pathways, centered around the SEL1L-HRD1 protein complex of ERAD, in the regulation of organellar organization in β cells. SEL1L-HRD1 ERAD deficiency in β cells triggers activation of autophagy, at least in part, via IRE1α (an endogenous ERAD substrate). In the absence of functional SEL1L-HRD1 ERAD, proinsulin is retained in the ER as high molecular weight conformers, which are subsequently cleared via ER-phagy. A combined loss of both SEL1L and autophagy in β cells leads to diabetes in mice shortly after weaning, with premature death by approximately 11 weeks of age, associated with marked ER retention of proinsulin and β cell loss. Using focused ion beam scanning electron microscopy powered by deep-learning automated image segmentation and 3D reconstruction, our data demonstrate a profound organellar restructuring with a massive expansion of ER volume and network in β cells lacking both SEL1L and autophagy. These data reveal at an unprecedented detail the intimate crosstalk among the 3 ER quality-control mechanisms in the dynamic regulation of organellar architecture and β cell function.

Excessive scar tissue formation along with bacterial infection, hemorrhage, and oxidative wound microenvironment pose adverse physiological and psychological effects on patients, which necessitate the advent of innovative anti-inflammatory, anti-bacterial, and anti-oxidative multifunctional wound dressings. The overarching objective of this study was to exploit bioactive glass (BG) and a natural anti-bacterial component namely "oregano essential oil (OEO)" to impart multifunctionality to poly(L-lactide-co-glycolide)/Gelatin (PLGA/Gel)-based nanofibrous dressings for excisional wound management. We performed a series of structural, morphological, and release studies as well as delineated angiogenic, hemostatic, anti-bacterial, and anti-oxidative properties of these bioactive dressings in vitro, which altogether revealed the beneficial effects of BG and OEO in terms of rapid hemostasis, improved chemotactic response, diminished bacterial colonization, and anti-inflammatory response. Impressively, in multiple injury models, including a rat tail-amputation model, an ear artery injury model, and a liver trauma model in rabbit in vivo, we reported BG-mediated rapid hemostasis. Moreover, dressings containing BG showed improved hemocompatibility and suppressed coagulation as revealed by activated partial thromboplastin assay (APTT) in vitro. In addition, the transplantation of these nanofibrous dressings in a full-thickness excisional wound model in rats showed significant tissue regeneration as evidenced by the more number of blood vessels, glands, and hair follicles, re-epithelialization, diminished inflammatory response, and less fibrotic tissue formation. Taken together our approach of simultaneously harnessing economical BG and OEO to enable multifunctionality to nanofibrous dressings for tissue repair may hold great promise for wound healing as well as other bio-related disciplines.

Dysregulation of the immune system is a cardinal feature of opioid addiction. Here, we characterize the landscape of peripheral immune cells from patients with opioid use disorder and from healthy controls. Opioid-associated blood exhibited an abnormal distribution of immune cells characterized by a significant expansion of fragile-like regulatory T cells (Tregs), which was positively correlated with the withdrawal score. Analogously, opioid-treated mice also showed enhanced Treg-derived interferon-γ (IFN-γ) expression. IFN-γ signaling reshaped synaptic morphology in nucleus accumbens (NAc) neurons, modulating subsequent withdrawal symptoms. We demonstrate that opioids increase the expression of neuron-derived C-C motif chemokine ligand 2 (Ccl2) and disrupted blood-brain barrier (BBB) integrity through the downregulation of astrocyte-derived fatty-acid-binding protein 7 (Fabp7), which both triggered peripheral Treg infiltration into NAc. Our study demonstrates that opioids drive the expansion of fragile-like Tregs and favor peripheral Treg diapedesis across the BBB, which leads to IFN-γ-mediated synaptic instability and subsequent withdrawal symptoms.

The critical heat flux (CHF) of flow boiling in a mini-channel is vital for equipment safety, but the boiling crisis triggering mechanism has been proved unsatisfactory. In this study, the VOSET method is adopted to investigate CHF of subcooled flow boiling in a vertical rectangular mini-channel by considering the conjugated heat transfer and using a reasonable nucleation site density model. Hundred of bubbles are accurately captured, and the evolutions of flow pattern, dry patch, and wall superheating are reproduced. Based on those, the relationship between boiling crisis and dry patch is demonstrated. When the heat flux is lower, some middle-sized isolated bubbles adhere to the wall surface with a dry patch below. This dry patch can be rewetted quickly. Hence, the wall superheating increases slightly along the flow direction and is within control. With the increasing heat flux, the dry patch expands because some big bubbles merge into the elongated bubble, leading to the local heat transfer deterioration, but the local wall superheating rise is still limited due to heat conduction inside the solid wall and the rewetting effect. However, the continuous coalescence of elongated bubbles midstream and downstream causes the appearance of an almost permanent dry patch with a high local wall superheating of 183.04 K near the outlet of the mini-channel when the heat flux rises to 500 kW/m2, which has exceeded the CHF of 375 kW/m2 obtained in this study. This triggering mechanism of the flow boiling crisis is new and different from the traditional ones. Besides, the departure from nucleate boiling (DNB) is found at 325 kW/m2, beyond which the wall superheating increases rapidly with heat flux.

Generating images from hand-drawings is a crucial and fundamental task in content creation. The translation is difficult as there exist infinite possibilities and the different users usually expect different outcomes. Therefore, we propose a unified framework supporting a three-dimensional control over the image synthesis from sketches and strokes based on diffusion models. Users can not only decide the level of faithfulness to the input strokes and sketches, but also the degree of realism, as the user inputs are usually not consistent with the real images. Qualitative and quantitative experiments demonstrate that our framework achieves state-of-the-art performance while providing flexibility in generating customized images with control over shape, color, and realism. Moreover, our method unleashes applications such as editing on real images, generation with partial sketches and strokes, and multi-domain multi-modal synthesis.

Tissue engineering (TE) has attracted the widespread attention of the research community as a method of producing patient-specific tissue constructs for the repair and replacement of injured tissues. To date, different types of scaffold materials have been developed for various tissues and organs. The choice of scaffold material should take into consideration whether the mechanical properties, biodegradability, biocompatibility, and bioresorbability meet the physiological properties of the tissues. Owing to their broad range of physico-chemical properties, inorganic materials can induce a series of biological responses as scaffold fillers, which render them a good alternative to scaffold materials for tissue engineering (TE). While it is of worth to further explore mechanistic insight into the use of inorganic nanomaterials for tissue repair, in this review, we mainly focused on the utilization forms and strategies for fabricating electrospun membranes containing inorganic components based on electrospinning technology. A particular emphasis has been placed on the biological advantages of incorporating inorganic materials along with organic materials as scaffold constituents for tissue repair. As well as widely exploited natural and synthetic polymers, inorganic nanomaterials offer an enticing platform to further modulate the properties of composite scaffolds, which may help further broaden the application prospect of scaffolds for TE.

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

The microlayer evaporation below the vapor bubble contributes much to heat dissipation and bubble growth, but it is hard to explore this microcosmic phenomenon. This study proposes a method for investigating the subcooled flow boiling heat transfer in a rectangular channel by considering the microlayer, conjugated heat transfer, a reasonable nucleation site density, and an accurate liquid-vapor interface. The implementation procedure of the microlayer model in the numerical simulation is fully demonstrated. Based on that, the bubble growth, flow pattern, heat transfer, microlayer depletion, evolutions of evaporative heat flux and dry patch during the subcooled flow boiling under different initial microlayer thicknesses are presented. Results indicate that microlayer evaporation contributes much to bubble volume and heat dissipation. The vapor volume generated by the microlayer evaporation exceeds that flows out of the channel because of the condensation effect at the liquid-vapor interface induced by the subcooled liquid, indicating bubble growth and expansion are completely attributed to microlayer evaporation. Simultaneously, much heat dissipates from the heat source due to microlayer evaporation, which contributes over 70% to both local and whole heat transfer. Because of microlayer depletion, some dry patches may appear at the elongated bubble tail. Therefore, liquid slug, elongated bubble, and dry patch circulate in the studied mini-channel, corresponding to heat transfer modes of liquid convection, microlayer evaporation, and vapor convection, supporting the three-zone heat transfer model. In addition, the initial microlayer thickness is related to the thermal resistance and affects the microlayer evaporation rate, leading to different flow patterns and heat transfer characteristics. The initial microlayer thickness is related to the slipping velocity of bubbles based on the Taylor model, which is recommended for the flow boiling study in a mini-channel.

Polymer-based piezoelectric composites (PPCs) demonstrate superior mechanical-vibrational energy harvesting and dissipating (EHD) capabilities. Piezoelectric materials endow the composites with the ability to convert mechanical vibrations into electrical signals that are collected and dissipated into Joule heat to increasing the damping behavior progressively. Conversely, the polymer matrix provides flexibility for fabricating wearable nanogenerators or transducers, and the viscoelastic properties of polymers offer the prominent damping ability of composites. The difference between the shunt circuits that simulate the EHD abilities of composites is based on the existence of a dissipating resistance. This paper discusses the EHD behaviors of PPCs based on the simulation of shunt circuits. The commonalities and differences between EHD behaviors in PPCs are presented. Certain impressive studies on composites used in wearable nanogenerators are presented. Moreover, applications of passive and active vibration attenuation systems and materials, and applications of PPCs with EHD behaviors are introduced. Through this review, we aim to establish the common aspects in the piezoelectric EHD behaviors, illustrate design strategies, and highlight the future exploration of novel EHD piezoelectric composites with multifunctional polymer matrices.

Two neutral polysaccharides (PPP1-1 and PPP1-2) were purified from persimmon peel. PPP1-1 (21.84 kDa) was mainly composed of arabinose (22.92 %), galactose (21.09 %), glucose (35.13 %), and xylose (19.09 %), while PPP1-2 (10.42 kDa) mainly contained arabinose (32.98 %), galactose (20.81 %), glucose (26.86 %), xylose (10.46 %), and mannose (7.63 %). Methylation and NMR spectra analysis demonstrated that the backbone of PPP1-1 appeared to be →6)-α-D-Glcp-(1→, →2,6)-α-D-Glcp-(1→, →5)-α-L-Araf-(1→, and →3,5)-α-L-Araf-(1 → residues with branches consisting of →3)-α-L-Araf-(1→, →4)-α-D-Glcp-(1→, →3)-β-D-Galp-(1→, →4)-β-D-Galp-(1→, →4)-β-D-Xylp-(1→, →6)-β-D-Galp-(1→, →4)-β-D-Manp-(1→, and α-L-Araf-(1 → residues. The main chain of PPP1-2 was composed of →6)-α-D-Glcp-(1→, →5)-α-L-Araf-(1→, and →3,5)-α-L-Araf-(1 → residues with branches consisting of →3)-α-L-Araf-(1→, →1,2)-α-D-Glcp-(6→, →4)-α-D-Glcp-(1→, →3)-β-D-Galp-(1→, →4)-β-D-Galp-(1→, →6)-β-D-Galp-(1→, →4)-β-D-Xylp-(1→, →4,6)-α-D-Glcp-(1→, and →4)-β-D-Manp-(1 → residues and terminal of α-L-Araf-(1 → residue. PPP1-2 exhibited stronger antioxidant activities and better thermal stability than PPP1-1. Our results provided the foundation for further investigating the structure and biological activities of persimmon peel polysaccharides and highlighted their potential to become potential antioxidants in functional food.

<h2>Summary</h2> Hydrogels offer great potential for the development of soft actuators and robots owing to their water-rich structures, remarkable biocompatibility, and responsiveness to various stimuli, making them suitable for a wide range of applications. However, conventional isotropic hydrogels have limited actuation performance, hindering their functionality and practical utility. The design and synthesis of anisotropic hydrogels present a promising approach for creating high-performance soft actuators and robots. In this review, we provide an overview of the key principles involved in fabricating bio-inspired anisotropic hydrogels. We also explore the various actuation methods employed in related actuators and discuss their potential applications in soft actuators and robots. Representative research from each category is examined, highlighting the advantages and disadvantages of each approach. Furthermore, we delve into the development of intelligent hydrogel actuators and robots, showcasing their multi-functionality. Finally, we address future research challenges and provide an outlook on the field of anisotropic hydrogels.

The escalating prevalence of anterior cruciate ligament (ACL) injuries in sports necessitates innovative strategies for ACL reconstruction. In this study, we propose a multiphasic bone-ligament-bone (BLB) integrated scaffold as a potential solution. The BLB scaffold comprised two polylactic acid (PLA)/deferoxamine (DFO)@mesoporous hydroxyapatite (MHA) thermally induced phase separation (TIPS) scaffolds bridged by silk fibroin (SF)/connective tissue growth factor (CTGF)@Poly(l-lactide-co-ε-caprolactone) (PLCL) nanofiber yarn braided scaffold. This combination mimics the native architecture of the ACL tissue. The mechanical properties of the BLB scaffolds were determined to be compatible with the human ACL. In vitro experiments demonstrated that CTGF induced the expression of ligament-related genes, while TIPS scaffolds loaded with MHA and DFO enhanced the osteogenic-related gene expression of bone marrow stem cells (BMSCs) and promoted the migration and tubular formation of human umbilical vein endothelial cells (HUVECs). In rabbit models, the BLB scaffold efficiently facilitated ligamentization and graft-bone integration processes by providing bioactive substances. The double delivery of DFO and calcium ions by the BLB scaffold synergistically promoted bone regeneration, while CTGF improved collagen formation and ligament healing. Collectively, the findings indicate that the BLB scaffold exhibits substantial promise for ACL reconstruction. Additional investigation and advancement of this scaffold may yield enhanced results in the management of ACL injuries.

The self-aggregation of amyloid-β (Aβ) and tau proteins are closely implicated in Alzheimer's disease (AD). Recent evidence indicates that Aβ and tau proteins can cross-interact to form co-aggregates, which aggravates the development of AD. However, their transient heterooligomer conformations and co-aggregation molecular mechanisms are largely unknown. Herein, we utilize replica exchange molecular dynamics simulations to investigate the conformational ensembles formed by the central hydrophobic core of Aβ (Aβ16–22) and each of two fibril-nucleating core segments of tau (PHF6* and PHF6). Both PHF6 and PHF6* are found to co-aggregate with Aβ16–22 into β-sheet-rich heterooligomers. Intriguingly, PHF6 and Aβ16–22 peptides formed closed β-barrels, while PHF6* and Aβ16–22 formed open β-barrels, implying their distinct co-aggregation property. Compared to Aβ16–22-PHF6*, Aβ16–22-PHF6 heterooligomers have higher β-sheet content, and contain longer β-strands and larger β-sheets, indicative of stronger co-aggregation ability of PHF6 with Aβ16–22. Further analyses reveal that hydrophobic and π-π stacking interactions between Y310 of PHF6 and Aβ16–22 are crucial for the closed β-barrel/larger β-sheet formation in Aβ16–22-PHF6 heterooligomers. These results highlight the paramount importance of PHF6 fragment, particularly Y310 residue, as a potential target for inhibiting Aβ-tau co-aggregation, which could help for effective therapeutic design in mitigating Aβ-tau co-aggregation related amyloidogenesis.

Steviol glycoside (SG) is a potential natural sugar substitute. The taste of various SG structures differ significantly, while their mechanism has not been thoroughly investigated. To investigate the taste mechanism, molecular docking simulations of SGs with sweet taste receptor TAS1R2 and bitter taste receptor TAS2R4 were conducted. The result suggested that four flexible coils (regions) in TAS1R2 constructed a geometry open pocket in space responsible for the binding of sweeteners. Amino acids that form hydrogen bonds with sweeteners are located in different receptor regions. In bitterness simulation, fewer hydrogen bonds were formed with the increased size of SG molecules. Particularly, there was no interaction between RM and TAS2R4 due to its size, which explains the non-bitterness of RM. Molecular dynamics simulations further indicated that the number of hydrogen bonds between SGs and TAS1R2 was maintained during a simulation time of 50 ns, while sucrose was gradually released from the binding site, leading to the break of interaction. Conclusively, the high sweetness intensity of SG can be attributed to its durative concurrent interaction with the receptor's binding site, and such behavior was determined by the structure feature of SG.

Parkinson's disease (PD) is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotective effects of total fl avonoids extracted from A. membranaceus (TFA) and their protective mechanisms.TFA offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the mouse model of Parkinsonism, by improving behavior performance in the gait analysis and pole test, and inhibiting the decline of tyrosine hydroxylase (TH) positive neurons and TH protein expression in substantia nigra of mice.TFA also prevented 1-methyl-4-phenylpyridinium (MPP + ) induced neurotoxicity in SH-SY5Y cells, by increasing GSH and GSH/GSSG ratio, and reducing reactive oxygen species.In addition, the neuroprotective effects of TFA were associated with its ability to restore MPTP/MPP + induced downregulation of SLC7A11 and glutathione peroxidase 4 (GPX-4).In conclusion, we demonstrated that TFA exerted signifi cant neuroprotection against MPTP/MPP + induced neurodegeneration by inhibiting ferroptosis through the regulation of SLC7A11/GPX-4 axis, suggesting the use of TFA as a possible food supplement in the prevention of PD.

The LiFePO4 battery module will generate a lot of heat in its working process. A method of combination air-cooling and liquid cooling can dissipate this heat, so that to keep optimal operating temperature range for battery module. However, designing a combination that can maximize the heat dissipation effect remains a challenging task due to the involvement of numerous parameters. Finally, an optimal solution is proposed based on the orthogonal optimization design approach, including the fin length, coolant mass flow rates, coolant temperature. The simulation results indicate that the average temperature difference of the cell was reduced by 14.03 % and the temperature difference of the cooling channel was reduced by 46.41 %. Besides, the cell temperature was further controlled by optimizing the air-cooling conditions. The results showed that when the air-cooling maintained the average temperature difference of the cell less than 5 °C, then the temperature difference of the cooling channel was only 1.084 °C. This scheme provides a reference for the optimization of large-capacity battery module temperature.

Anode-free sodium batteries (AFSBs) with high energy density and cost-efficiency are practically promising for the transition to clean-energy society. However, application is limited because of low coulombic efficiency (CE) and limited cycle-life, together with a lack of understanding in device energy density and cost. Here we report a critical assessment of selected AFSBs with lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) from energy density and cost perspectives, based on commercial 4680 cylindrical construction. We establish reasons for low cycle-life of AFSBs and summarize current research in AFSBs. We confirm energy density range, materials cost, and potential demand for AFSBs via computation based on 4680 battery devices. We show the impact of active sodium ions and cathode active sites on cycle life. We compare the improvements in cycle-life achieved though electrolyte innovation, artificial solid electrolyte interphase (SEI) engineering, current collector modification, and pre-sodiation, along with the resulting energy density. We provide perspectives on likely future research to boost practical application of AFSBs. We conclude that findings will be of benefit in design for anode-free sodium batteries for clean energy storage and of interest therefore to a range of researchers in electrochemistry, materials and device engineering.

Boiling is an efficient heat transfer mode with significant potential for thermal management in high-power electronic equipment. However, a comprehensive understanding of the boiling process, which encompasses bubble nucleation, growth, coalescence, slipping, and detachment across various scales, remains challenging. Molecular dynamics simulation, lattice Boltzmann, and computational fluid dynamics methods are popular and powerful tools for investigating boiling heat transfer phenomena at microscopic, mesoscopic, and macroscopic scales. These methods enable researchers to uncover the underlying boiling mechanisms and propose heat transfer enhancement techniques. Therefore, this paper provides a comprehensive review of boiling heat transfer, spanning from atomistic to mesoscopic and macroscopic scales, utilizing these three numerical methods. It addresses critical issues related to nanoscale bubble nucleation mechanisms, pool boiling, and flow boiling, and proposes potential solutions and future researches, supplementing our previous review [Some advances in numerical simulations of multiscale heat transfer problems and particularly for boiling heat transfer, Annu. Rev. Heat Transf., 6 (2022) 217–269]. Besides, by shedding light on the characteristics of these numerical methods in studying boiling heat transfer, this paper aims to foster their development and advance enhanced heat transfer technologies.

We hypothesize that the first step of aggregation of disordered proteins, such as α-synuclein, is controlled by the rate of backbone reconfiguration. When reconfiguration is fast, bimolecular association is not stable, but as reconfiguration slows, association is more stable and subsequent aggregation is faster. To investigate this hypothesis, we have measured the rate of intramolecular diffusion in α-synuclein, a protein involved in Parkinson’s disease, under solvent conditions that accelerate or decelerate aggregation. Using the method of tryptophan-cysteine (Trp-Cys) quenching, the rate of intramolecular contact is measured in four different loops along the chain length. This intrinsically disordered protein is highly diffusive at low temperature at neutral pH, when aggregation is slow, and compacts and diffuses more slowly at high temperature or low pH, when aggregation is rapid. Diffusion also slows with the disease mutation A30P. This work provides unique insights into the earliest steps of α-synuclein aggregation pathway and should provide the basis for the development of drugs that can prevent aggregation at the initial stage.

The intraventricular hemorrhage (IVH) secondary to intracerebral hemorrhage (ICH) was reported to be relevant to a higher incidence of hydrocephalus, which would result in poorer outcomes for patients with ICH. However, the mechanisms responsible for this relationship remain poorly characterized. Thus, this study was designed to further explore the development and progression of hydrocephalus after secondary IVH.Autologous blood injection model was induced to mimic ICH with ventricular extension (ICH/IVH) or primary IVH in Sprague-Dawley rats. Magnetic resonance imaging, Morris water maze, brain water content, Evans blue extravasation, immunohistochemistry staining, Western blot, iron determination, and electron microscopy were used in these rats. Then, deferoxamine treatment was used to clarify the involvement of iron in the development of hydrocephalus.Despite the injection of equivalent blood volumes, ICH/IVH resulted in more significant ventricular dilation, ependymal cilia damage, and iron overload, as well as more severe early brain injury and neurological deficits compared with IVH alone. Systemic deferoxamine treatment more effectively reduced ventricular enlargement in ICH/IVH compared with primary IVH.Our results show that ICH/IVH caused more significant chronic hydrocephalus and iron accumulation than primary IVH alone. Intracerebral hematoma plays a vital role in persistent iron overload and aggravated hydrocephalus after ICH/IVH.

The modulation of DNA accessibility by nucleosomes is a fundamental mechanism of gene regulation in eukaryotes. The nucleosome core particle (NCP) consists of 147 bp of DNA wrapped around a symmetric octamer of histone proteins. The dynamics of DNA packaging and unpackaging from the NCP affect all DNA-based chemistries, but depend on many factors, including DNA positioning sequence, histone variants and modifications. Although the structure of the intact NCP has been studied by crystallography at atomic resolution, little is known about the structures of the partially unwrapped, transient intermediates relevant to nucleosome dynamics in processes such as transcription, DNA replication and repair. We apply a new experimental approach combining contrast variation with time-resolved small angle X-ray scattering (TR-SAXS) to determine transient structures of protein and DNA constituents of NCPs during salt-induced disassembly. We measure the structures of unwrapping DNA and monitor protein dissociation from Xenopus laevis histones reconstituted with two model NCP positioning constructs: the Widom 601 sequence and the sea urchin 5S ribosomal gene. Both constructs reveal asymmetric release of DNA from disrupted histone cores, but display different patterns of protein dissociation. These kinetic intermediates may be biologically important substrates for gene regulation.

Background and Purpose— Hyperbaric oxygen (HBO) has been reported to be neuroprotective and to improve neurofunctional outcomes in acute stroke. However, it is not clear whether delayed HBO enhances endogenous neurogenesis and promotes neurofunctional recovery. The aim of this study is to evaluate the effects of delayed HBO therapy on neurogenesis and its potential mechanisms. Methods— One hundred eleven male Sprague–Dawley rats that survived for 7 days from 2 hours of middle cerebral artery occlusion and reperfusion were used. Delayed and multiple HBO were administrated beginning at 7 days after middle cerebral artery occlusion and lasting for 42 days with 3 HBO-free intervals (5 days each). Motor sensory deficits were measured by foot-fault test, and learning and memory abilities were evaluated by Morris water maze. Neurogenesis was examined by double immunostaining of bromodeoxyuridine and doublecortin, bromodeoxyuridine and neuronal nuclei at day 42. For mechanism studies, inhibitors for reactive oxygen species (ROS), hypoxia-inducible factor (HIF)-1α, and β-catenin were administrated, and the levels of ROS, HIF-1α, β-catenin, lymphoid enhancer–binding factor-1, T-cell factor-1, neurogenin-1, doublecortin, and synapsin-1 were assessed by ELISA or Western blot at day 14. Results— Delayed HBO treatment promoted neurogenesis and improved neurofunctional recovery at day 42, and the improvements were reversed by inhibition of ROS and HIF-1α. Delayed HBO significantly increased ROS and HIF-1α, and upregulated the expression of neurogenin-1, doublecortin, and synapsin-1. Inhibition of ROS and HIF-1α removed the effects of delayed HBO. Conclusions— Delayed HBO enhanced endogenous neurogenesis and improved neurofunctional recovery in the late-chronic phase of stroke possibly mediated by ROS/HIF-1α/β-catenin pathway. Delayed HBO may serve as an alternative treatment to improve long-term recovery of stroke survivors.