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Student performance prediction is vital for identifying at-risk students and providing support to help them succeed academically. In this paper, we propose a feature importance-based multi-layer CatBoost approach to predict the students’ grade in the period exam. The idea is to construct a multi-layer structure with increasingly important features layer by layer. Specifically, the feature importance are first calculated and sorted in ascending order. In each layer, features with the least importance are accumulated until reaching a given threshold. Then, these selected features are used to construct the first layer by training the CatBoost. Next, this trained CatBoost is utilized to generate a feature that adds to the feature set with their importance within a threshold. After that, all these feature are used to train the CatBoost in the next layer. This process is repeated until all the features are used. The results show that the proposed model has the best performance. Moreover, the statistical test conducted based on 20-runs of experiments validates the significant superiority of our proposed model over the compared models and demonstrates the efficacy of the multi-layer structure in enhancing the proposed model. This indicates our proposed model can help decision makers in enhancing educational quality.

Heterostructure engineering provides versatile platforms for exploring exotic physics and enhancing the device performance through interface coupling. Despite the rich array of physical phenomena presented by heterostructures composed of semiconductor and metal van der Waals materials, significant gaps remain in understanding their optical, thermal, and electronic properties. Here, we demonstrate that the valley pseudospin and electron–phonon coupling in monolayer WSe2are significantly influenced by interface coupling with 1T-VSe2. The heterointerface alters the relaxation process of valley excitons, leading to a transition in magnetic-field-dependent valley polarization from a linear to a “V” shape. Furthermore, we uncover that enhanced electron–phonon coupling exacerbates variations in exciton and valley exciton behavior with temperature, involving higher phonon energies and a shift from acoustic to optical phonons. These findings highlight a promising pathway to manipulate valley excitons and investigate electron–phonon coupling through van der Waals interface interactions.

IV–V two-dimensional materials have emerged as key contenders for polarization-sensitive and angle-resolved devices, given their inherent anisotropic physical properties. While these materials exhibit intriguing high-pressure quasi-particle behavior and phase transition, the evolution of quasi-particles and their interactions under external pressure remain elusive. Here, employing a diamond anvil cell and spectroscopic measurements coupled with first-principles calculations, we unveil rarely observed pressure-induced phonon–phonon coupling in layered SiP flakes. This coupling manifests as an anomalous phonon hardening behavior for the A1mode within a broad wavenumber phonon softening region. Furthermore, we demonstrate the effective tuning of exciton emissions in SiP flakes under pressure, revealing a remarkable 63% enhancement in the degree of polarization (DOP) within the pressure range of 0–3.5 GPa. These findings contribute to our understanding of high-pressure phonon evolution in SiP materials and offer a strategic approach to manipulate the anisotropic performance of in-plane anisotropic 2D materials.

Quinolones, a widely used class of antibiotics, present significant environmental and health concerns if they excessively remain in the environment and in food. Aptamers specific to quinolones can be applied as bioreceptors for the detection of quinolone residues in the environment and food. The quinolone family contains dozens of different individuals that share the same core structure coupled with various substituents at six different positions. The diversity and complexity of the substitution sites make it a challenge to choose a set of representative molecules that encompass all the desired sites and preserve the core molecular framework for the screening of quinolone-specific aptamers via systematic evolution of ligands by exponential enrichment (SELEX). To address this challenge, we introduce a novel parallel-series strategy guided by Liebig’s law for isolating quinolone-specific cross-reactive aptamers by using the library-immobilized SELEX method. Through this approach, we successfully identified 5 aptamers (Apt.AQ01–Apt.AQ05) with high binding affinity and excellent specificity to 24 different quinolone individuals. Among them, Apt.AQ03 showcased optimal performance with affinities ranging from 0.14 to 1.07 μM across the comprehensive set of 24 quinolones, exhibiting excellent specificity against nontarget interferents. The binding performance of Apt.AQ03 was further characterized with microscale thermophoresis, circular dichroism spectra, and an exonuclease digestion assay. By using Apt.AQ03 as a bioreceptor, a fluorescence resonance energy transfer (FRET) aptasensor was developed for the detection of 24 quinolones in milk, achieving a remarkable detection limit of 14.5–21.8 ng/mL. This work not only establishes a robust and effective strategy for selecting cross-reactive aptamers applicable to other small-molecule families but also provides high-quality aptamers for developing various high-throughput and reliable methods for the detection of multiple quinolone residues in food.

Deep ultraviolet photodetectors play a critical role in applications such as ozone layer monitoring and missile alert systems. This work investigates the potential of graphene quantum dots to enhance deep ultraviolet light photodetection within the graphene/Si heterojunction. The addition of graphene quantum dots not only reduces the Schottky barrier between graphene and Si but also enhances the absorption ability of deep ultraviolet light by graphene and Si. As a result, the modified junction exhibited exceptional performance metrics, including a notable responsivity of 0.21 A/W, an impressive specific detectivity of ${1}.{13}\times {10} ^{{11}}$ Jones, substantial external quantum efficiency of 94.5 %, and swift response speed (23.7/47.4 ns). Elevating the reverse bias voltage increases electron kinetic energy, thereby inducing collision ionization effects in Si. Subsequent evaluations revealed a high responsivity value of 31.4 A/W and a good gain of 28, affirming the capability of the device to detect faint light signals. The successful utilization of the Gr QDs/Gr/Si heterojunction as a single-pixel imaging device underscored its prowess in imaging applications. This innovative hybrid approach opens avenues for large-scale fabrication and diverse applications in optoelectronic devices.

Abstract: In this report, a novel chemical synthesis of polyaniline/gold nanocomposite is explored using ionic liquid (IL) 1-Butyl-3-methylimidazolium hexafluorophosphate. The direct chemical synthesis of polyaniline/gold nanocomposite was initiated via the spontaneous oxidation of aniline by AuCl4− in IL. A nearly uniform dispersion of polyaniline/Au particles with a diameter of 450 ± 80 nm was produced by this method, which indicates that this method is more suitable for controlling particle dimensions. It was also found that the electrical conductivity of the polyaniline/gold nanocomposite was more than 100 times higher than that of the pure polyaniline nanoparticles. The polyaniline/gold nanocomposite displays superior function in the biocatalytic activation of microperoxidase-11 because of the high surface area of the assembly and the enhanced charge transport properties of the composite material. We also report the possible application of polyaniline/gold nanocomposite as a H2O2 biosensor.

Understanding the groundwater natural background levels (NBLs) is important in distinguishing groundwater contamination and guiding the groundwater management. Groundwater environment in suburb areas around the large city may suffer from strong impact of human activity during rapid urbanization which will have significant effect on the groundwater natural background levels. Although many previous studies have proposed different methods to understand the spatial distribution of NBLs, its temporal evolution and the relationship with groundwater quality is not well understood. In this study, we investigated the long-term evolution of NBLs and groundwater hydrochemical anomalies in the 59 wells of the Pinggu basin by combining the comprehensive groundwater hydrochemical anomalies identification and groundwater quality assessment. NO3−, Cl−, and SO42−were found to be as the major chemical constitutions demonstrating the strong anomaly degree, which decreased over time. The zoning and evolution of groundwater quality also aligned with the variation of anomaly areas. Regions with a higher degree of abnormality were consistent with those with poorer groundwater quality. The impact of human activities on the groundwater environment decreased in the Pinggu basin compared to the initial years due to the efforts of environment protection and governance by the local government. Investigating the temporal and spatial variation, hydrochemical properties by combination of NBLs and groundwater quality assessment provided a useful approach to understand groundwater environment in rapidly urbanizing areas.

The objective of this meta-analysis was to systematically review existing evidence and evaluate variations in levels of circulating endothelial progenitor cells (EPCs) among individuals with psoriatic arthritis (PsA), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA). Relevant studies were identified through database searches, and 20 records were enrolled. We used the fixed-effect model or random-effect model to estimate the pooled standardized mean difference (SMD) with 95% confidence intervals (CIs) in circulating EPC levels between inflammatory arthritis patients and controls. The results showed that circulating EPC levels differed among subtypes of inflammatory arthritis, with significantly lower levels in patients with RA (SMD = −0.848, 95% CI = −1.474 to −0.221, p = 0.008) and PsA (SMD = −0.791, 95% CI = −1.136 to −0.446, p < 0.001). However, no statistically significant difference was found in circulating EPC levels between patients with JIA and controls (SMD = −1.160, 95% CI = −2.578 to 0.259, p = 0.109). Subgroup analyses suggested that in patients with RA, circulating EPC levels were influenced by age, disease activity, and duration. Although many studies have investigated circulating EPC levels in patients with inflammatory arthritis, the results have been inconsistent. This meta-analysis offers a comprehensive overview of the existing evidence and emphasizes the association between levels of circulating EPCs and various types of arthritis. However, further research is needed to determine the specific mechanisms underlying the observed differences in EPC levels in different types of arthritis and to establish the clinical utility of this biomarker.

Moiré superlattices have emerged as a promising platform for investigating and designing optically generated excitonic properties. The electronic band structure of these systems can be qualitatively modulated by interactions between the top and bottom layers, leading to the emergence of new quantum phenomena. However, the inhomogeneities present in atomically thin bilayer moiré superlattices created by artificial stacking have hindered a deeper understanding of strongly correlated electron properties. In this work, we report the fabrication of homogeneous moiré superlattices with controllable twist angles using a 2L-WSe2/2L-WSe2homostructure. By adding extra layers, we provide additional degrees of freedom to tune the optical properties of the moiré superlattices while mitigating the nonuniformity problem. The presence of an additional bottom layer acts as a buffer, reducing the inhomogeneity of the moiré superlattice, while the encapsulation effect of the additional top and bottom WSe2monolayers further enhances the localized moiré excitons. Our observations of alternating circularly polarized photoluminescence confirm the existence of moiré excitons, and their characteristics were further confirmed by theoretical calculations. These findings provide a fundamental basis for studying moiré potential correlated quantum phenomena and pave the way for their application in quantum optical devices.

Moiré superlattices induced by twisted van der Waals (vdW) heterostructures or homostructures have recently gained significant attention due to their potential to generate exotic strong-correlation electronic and phonon phenomena. However, the lack of dynamic tuning for interlayer coupling of moiré superlattices hinders a thorough understanding and development of the moiré correlation state. Here, we present a dynamic tuning method for twisted WSe2/WSe2homobilayers using a diamond anvil cell (DAC). We demonstrate the powerful tuning of interlayer coupling and observe an enhanced response to pressure for interlayer breathing modes and the rapid descent of indirect excitons in twisted WSe2/WSe2homobilayers. Our findings indicate that the introduction of a moiré superlattice for WSe2bilayers gives rise to hybridized excitons, which lead to the different pressure-evolution exciton behaviors compared to natural WSe2bilayers. Our results provide a novel understanding of moiré physics and offer an effective method to tune interlayer coupling of moiré superlattices.

To investigate the relationship between sleep disturbance, catastrophizing, and knee pain in middle‐aged and older individuals. Data from the Osteoarthritis Initiative cohort from months 48 to 96 were used, where month 48 was treated as baseline. Knee pain (Western Ontario and McMaster Universities Osteoarthritis Index pain scale score ≥5 [range 0–20]), catastrophizing (extracted from Coping Strategies Questionnaire score ≥3 [range 0–6]), and sleep quality (extracted from Center for Epidemiologic Studies Depression Scale [range 1–4]) were assessed annually. We described the association of sleep disturbance with the presence and risk of knee pain and catastrophizing. The mediation effect of knee pain and catastrophizing on the sleep–catastrophizing and sleep–pain association was evaluated, respectively. Catastrophizing and knee pain were reported in 346 (10%) and 917 (24%) of the 3,813 participants (mean 64.9 years, 58% female) at baseline. Participants with worse sleep disturbance were more likely to have knee pain (prevalence ratio [PR] 1.4–2.0, Pfor trend <0.001) and catastrophizing (PR 1.4–3.1, Pfor trend <0.001). Sleep disturbance at baseline predicted the risk of knee pain (risk ratio [RR] 1.1, Pfor trend <0.001) and catastrophizing (RR 1.2–1.7, Pfor trend <0.001) during follow‐up. No statistically significant interactions between sleep disturbance and knee pain or catastrophizing were observed. Knee pain and catastrophizing mediated the sleep–catastrophizing and sleep–pain association, respectively, at baseline, and knee pain negatively mediated the sleep–catastrophizing association longitudinally. Sleep disturbance was associated with the presence and risk of catastrophizing and knee pain. Sleep interventions may have a universal and independent effect in preventing incident knee pain.

Biaxial fatigue testing is an effective way to verify the performance of large wind turbine blades. The test process will generate a large amount of transient strain data, which needs to be peak detection to control the loading system and provided it to third-party organizations for type certification. Peak detection is challenging due to the long test cycle and severe signal noise pollution. The objective of this article is to propose a strain data processing method based on morphological filtering. It is found that morphological filtering + three-point smoothing has a better filtering effect. In addition, a peak detection algorithm is designed and proved its effectiveness. In order to validate the proposed method, a principle prototype of biaxial fatigue testing is built for testing. The results show that the method can not only effectively filter out noise, but also accurately and quickly detect the strain peaks, improve the efficiency of damage calculation and effectively control the test process. The method can also be used in the practical engineering field to process strain data generated during fatigue testing of wind turbine blades and improve overall testing efficiency.

It is an urgent need to develop simple and high-throughput methods for simultaneously screening and detecting multiple or groups of sulfonamides (SAs) in animal-derived foods since various SAs were alternately used in animal husbandry to avoid generating drug resistance. We herein developed a novel HCl-reduced nicotinamide adenine dinucleotide I (NADH)-ascorbic acid (AA)-mediated gold nanobipyramids (AuNBPs) growth system, which can precisely regulate the growth rate of AuNBPs, to generate two colorful and stable AA-corresponding multicolor signal channels with different sensitivities. Based on the HCl-NADH-AA-mediated AuNBP growth system, we further developed a dual-channel multicolor immunoassay for simultaneously realizing rapid screening and detection of 5 SAs (sulfamethazine, sulfamethoxydiazine, sulfisomidine, sulfamerazine, and sulfamonomethoxine) by using a paper-based analytical device for sensitively and stably reading out the signal and a broad-specificity anti-SAs antibody as a bio-receptor. The developed immunoassay has more color changes, a wider linear range, excellent specificity and stability, and two multicolor signal channels (L-channel and H-channel) with different sensitivities. The H-channel exhibited 7–8 SAs-corresponding color changes and can be used to detect 5 target SAs with a visual detection limit of 0.1–0.5 ng/mL and a spectrometry detection limit of 0.05–0.16 ng/mL. The L-channel exhibited 7–9 SAs-corresponding color changes and can be used to detect 5 target SAs with a visual detection limit of 2.0–6.0 ng/mL and a spectrometry detection limit of 0.40–1.47 ng/mL. The developed immunoassay was successfully used to simultaneously screen and detect low-concentration and high-concentration of target SAs in milk and fish muscle samples with a recovery of 85–110% and an RSD (n= 5) < 8%. The visual detection limit of our immunoassay is much lower than the maximum residue limit of total SAs in edible tissue. All above features make our immunoassay a promising assay for simultaneously realizing the rapid screening and quantitative determination of multiple SA residues in food by bare eye observation. It must be mentioned that our immunoassay may be expended as a general method for the simultaneous visual screening and detection of other drugs using the corresponding antibody as a recognition probe.

In response to the issues of low efficiency and significant impact on blade intrinsic frequency posed by the current biaxial resonance blade fatigue testing method, an innovative dynamic characterization method based on a 2-DOF (two-degree-of-freedom) planar parallel testing device is proposed in this paper. Firstly, the kinematic forward and inverse solution equations of the mechanism are established by scrutinizing the inherent positional relationships that govern its operation. The velocity Jacobian matrix is derived, and three types of singularities prevalent in the mechanism are analyzed. Secondly, based on the kinematics of the mechanism, an analysis of its workspace is undertaken to subsequently determine the range of its motion. Thirdly, by applying the Lagrange equations, the kinetic model of the mechanism is established, which can capture the dynamic interplay of forces and accurately calculate the changes in angular displacement, angular velocity, and angular acceleration of the active joint. Finally, a virtual prototype model and kinematics simulation are conducted based on the mechanism dimensions and assembly mode. The results show that the angular velocity, angular acceleration, and torque of the active joint all demonstrate smooth and uninterrupted curves that align with the actual testing trajectories, confirming the accuracy and effectiveness of our approach.

CuS is a suitable material for use in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Nevertheless, the Zn2+reaction between CuS is challenging due to the high radius and the considerable electrostatic force between the Zn2+and CuS cathode. In this work, CuS nanosheets were in situ grown on a template surface via the hydrothermal method. The composition, surface morphology, and microstructure were then studied in detail. The zinc storage properties and mechanism were investigated through electrochemical testing, density functional theory and molecular dynamics simulation. The findings demonstrate that CuS nanosheets are formed in situ along the octahedral surface, resulting in the development of multistage structures. The distinctive configuration is capable of efficaciously preventing nanosheet aggregation, augmenting the specific surface area and active site of electrochemical reactions. Furthermore, the formation of a hollow structure through ion exchange reduces the intercalation energy barrier of Zn2+, facilitates rapid ion diffusion, enhances the charge transfer rate, and markedly improves battery performance.

Bend-twist coupling (BTC), a method of passive load alleviation for turbine blade, has a significant influence on blade mechanical properties. The coupling behavior between bending and twisting motions stems from the material anisotropy in blade laminate or from the unique blade geometry such as sweep, deflection, and pre-bending. The material-based approach is employed in this research to determine influence regularity of BTC design on blade mechanical properties. To begin with, the blade property analysis tool PreComp that integrates a shear flow method with the classical laminate theory is adopted to compute the cross-sectional stiffnesses of the blades with different degree of BTC effect. Next, the bend-twist coupling coefficients for the BTC blades with different fiber orientation are calculated. Finally, the remaining mechanical properties including static performance, modal characteristics and buckling limits for different BTC blades are determined by the finite element method and the influence of changes in the degree of BTC effect on all these mechanical properties is further evaluated. The results show that the BTC effect markedly influences the different mechanical properties of the blade in different patterns. The 20° BTC blade has the highest BTC coefficient and the edgewise BTC coefficient at 100 m is 2.5 times higher than the flapwise BTC coefficient, while the maximum value of the torsional modal frequency of 3.8429 Hz and the greatest critical buckling load of 4328.1 kN corresponds to the 10° BTC blade and the 15° BTC blade respectively.

As a combination concept of a 2D material and a superlattice, two-dimensional superlattices (2DSs) have attracted increasing attention recently. The natural advantages of 2D materials in their properties, dimension, diversity and compatibility, and their gradually improved technologies for preparation and device fabrication serve as solid foundations for the development of 2DSs. Compared with the existing 2D materials and even their heterostructures, 2DSs relate to more materials and elaborate architectures, leading to novel systems with more degrees of freedom to modulate material properties at the nanoscale. Here, three typical types of 2DSs, including the component, strain-induced and moiré superlattices, are reviewed. The preparation methods, properties and state-of-the-art applications of each type are summarized. An outlook of the challenges and future developments is also presented. We hope that this work can provide a reference for the development of 2DS-related research.

AbstractAs a relatively young additive manufacturing technology, Electron Beam Powder Bed Fusion (EB-PBF) attracts increasing attention in academics and industry. Especially, the last five years have seen an explosion in machine and process development as well as material research for EB-PBF. Compared to other additive manufacturing approaches, e.g., the more widely used laser powder bed fusion, EB-PBF shows various unique features and advantages for processing high-performance metallic components. In this article, recent advancements in the realm of EB-PBF over the past five years are reviewed.

Long-lived emissive nucleic acid probes are widely used in biochemical analysis due to their programmable structures, high signal-to-background ratio, and high sensitivity. Homogeneous detection based on long-lived emissive nucleic acid probes is often achieved through Förster resonance energy transfer (FRET), which suffers from the limitation of a narrow effective distance range. Herein, a new strategy of accessing nucleic acid hybridization-responsive luminescent probes is presented. The photoluminescence (PL) of a Lumi4-Tb complex internally modified with DNA is switched on by nucleic acid hybridization, after which the PL is increased up to 20 times. PL lifetime analysis revealed a possible mechanism of luminescence enhancement. Due to the flexibility of single-stranded nucleic acid chains, the bases and phosphate groups can coordinate with the Tb(III), which reduces the stability of the Tb complex and results in weak PL. After hybridization, the rigid double helix structure suppresses the coordination between Tb(III) and the bases or phosphate groups, causing luminescence enhancement. As the DNA sequence can be freely designed, an array of probes for different DNA or RNA targets can be created with the same Tb complex. Moreover, the novel probe design can afford pM detection limits of DNA or RNA without any nucleic acid amplification and exhibits great potential for nucleic acid detection in clinical diagnosis.

We present a convenient and efficient protocol to synthesize quinolines and quinazolines in one pot under mild conditions. A variety of substituted quinolines were synthesized in good to excellent yields (up to 97% yield) from the dehydrogenative cyclizations of 2-aminoaryl alcohols and ketones catalyzed by readily available Co(OAc)2·4H2O. This cobalt catalytic system also showed high activity in the reactions of 2-aminobenzyl alcohols with nitriles, affording various quinazoline derivatives (up to 95% yield). The present protocol offers an environmentally benign approach for the synthesis of N-heterocycles by employing an earth-abundant cobalt salt under ligand-free conditions.

Vitexin, one of the major active components in hawthorn, has been shown to possess multiple pharmacological activities. Here, we sought to investigate the effect of vitexin on an ameliorating dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) mouse model and further explored its potential mechanism. The results indicated that vitexin administration could significantly alleviate the signs of colitis via suppressing body weight loss, reducing disease activity index (DAI) score, and mitigating colonic damage. Also, vitexin treatment in colitis mice markedly inhibited the production of pro-inflammation cytokines (such as IL-1β, IL-6, and TNF-α). Meanwhile, vitexin also could markedly down-regulate the phosphorylation levels of p65, IκB, and STAT1. Moreover, vitexin also dose-dependently increased the expressions of muc-2, ZO-1, and occludin proteins in colonic tissues of colitis mice. Further studies revealed that vitexin dramatically modulated the disturbed intestinal flora in colitis mice. Vitexin is beneficial for regulating abundances of some certain bacteria, such as Bacteroides, Helicobacter, Alistipes, Lachnospiraceae_NK4A136_group, and Lachnospiraceae_UCG-006.Interestingly, the correlation analysis indicated that key microbes were strongly correlated with colitis features, such as pro-inflammatory cytokines and gut barrier. Collectively, these results demonstrated that vitexin treatment alleviated inflammation, intestinal barrier dysfunction, and intestinal flora dysbiosis in colitis mice. Vitexin is expected to be a promising compound for UC treatment.

Background: Connective tissue diseases (CTD), including systemic lupus erythematosus and rheumatoid arthritis (RA), have long been treated with hydroxychloroquine (HCQ). However, prolonged HCQ use poses a risk of adverse effects, particularly retinopathy.Objective: To detect early retinal changes assessed by optical coherence tomography angiography (OCTA) in CTD patients with long-term HCQ treatment and to explore the relationship between OCTA parameters and the concentrations of HCQ and its metabolites.Design: A cross-sectional study conducted from March 2020 to October 2021 at the First Affiliated Hospital of Anhui Medical University.Methods: The area and perimeter of the foveal avascular zone (FAZ), the thickness of the fovea and parafovea, and the vascular density of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in each area of the macula were measured by OCTA in 43 CTD patients treated with HCQ for over 6 months. Meantime, blood concentrations of HCQ and its metabolites were determined by high-performance liquid chromatography-tandem mass spectrometry, and the clinical documents of all 43 involved patients were collected.Results: There is no significant correlation between OCTA outcomes and the patient’s age, disease duration, and weight-dependent dose. HCQ cumulative duration positively correlated with FAZ area and perimeter (r= 0.419, p= 0.005 and r= 0.407, p= 0.007, respectively) and negatively correlated with the foveal vessel density in DCP (r= −0.378, p= 0.012). HCQ cumulative dose had a positive correlation with FAZ area and perimeter (r= 0.445, p= 0.003 and r= 0.434, p= 0.004, respectively) and had a negative correlation with foveal vessel density in SCP and DCP (r= −0.383, p= 0.011 and r= −0.424, p= 0.005, respectively). OCTA outcomes did not correlate with HCQ and its metabolite concentrations.Conclusion: OCTA could be used to detect microvascular changes in the macula of CTD patients with long-term HCQ therapy. It was not found the concentrations of HCQ and its metabolites were associated with retinal vascular changes.

In order to overcome the shortcoming of traditional strength modeling of glass fiber reinforced polymer (GFRP) composite laminates that require a large amount of strength test data, a strength degradation model on the account of residual stiffness degradation data is proposed. First, fatigue damage growth can be described by the gradual reduction of the stiffness and strength, and damage expressed by the two degradation methods are equivalent. Second, according this assumption, the connection between the two damage indices is established, and then a four parameters strength degradation model is obtained. Finally, the proposed model is validated by the applying experimental data of GFRP laminates, and the precision of proposed model is contrasted with other four models. Verification results indicate that if the residual stiffness degradation data is known, the residual strength degradation law can be predicted by a small number of residual strength tests and the presented model has better applicability and higher fitting accuracy.

Hydrogel strain sensors with extreme temperature tolerance have recently gained great attention. However, the sensing ability of these hydrogel strain sensors changes with temperature, resulting in the variety of output signals that causes signal distortion. In this study, double-network hydrogels comprising SiO2nanoparticles composed of polyacrylamide and phytic acid-doped polypyrrole were prepared and applied on strain sensors with a wide sensing range, high adhesiveness, and invariable strain sensitivity under flame and cold environments. The hydrogels had stable conductivity, excellent adhesive strength of up to 79.7 kPa on various substrates, and high elongation of up to 1896% at subzero temperature and after heating. They also exhibited effective flame retardancy with low surface temperature (71.2 °C) after 1200 s of heating (200 °C) and antifreezing properties at a low temperature of −20 °C. Remarkably, even under cold temperature and heat treatment, the hydrogel-based strain sensor displayed consistent sensing behaviors in detecting human motions with a broad strain range (up to 500%) and steady gauge factor (GF, ∼2.90). Therefore, this work paves the way for the applications of hydrogel sensors in robotic skin, human–mechanical interfaces, and health monitoring devices under harsh operating environments.

Interleukin-21 (IL-21) has been shown to play an important role in the immune system. This study aimed to investigate the changes in the level of IL-21 in patients with anti-neutrophil cytoplasmic antibodies against myeloperoxidase (MPO-ANCA)-associated vasculitis (MPO-AAV), as well as explore its influence on disease activity and the potential mechanism. Flow cytometry was performed to detect the percentage of follicular helper T cells (Tfh) among CD4+T cells (Tfh%); the percentage of Tfh-expressing inducible costimulator (ICOS) among Tfh cells (ICOS+Tfh%); the percentage of Tfh-expressing programmed cell death protein 1 (PD-1) among Tfh cells (PD-1+Tfh%); and mean fluorescence intensity of Tfh-expressing ICOS or PD-1 in the peripheral blood. An enzyme-linked immunosorbent assay was used to measure the levels of serum IL-21 and MPO-ANCA. The Birmingham Vasculitis Activity Score was used to evaluate disease activity. Our results revealed that the level of IL-21 in the patient group was significantly higher than that in the healthy control group (1324.0 ± 812.4 pg/mL vs. 704.2 ± 266.3 pg/mL, P< 0.001), and it was an independent factor affecting the disease activity (P= 0.022). Thus, blocking the activity of IL-21 may represent a potential novel target for the future treatment of MPO-AAV.

Organometallic complexes (OMCs) consisting of organic and metal active moieties have shown immense potential for application in solar cells. The diverse structure, rich porosity, and unique charge centers of OMCs enable them to be functional in solar cells. In this review, we introduced four types of OMCs, such as crown organometallic complexes, β‐diketone metal complexes, cyclometallic complexes, and main chain metal‐containing polymers, providing an in‐depth analysis of the structure‐performance relationship. OMCs could serve as active or interlayer materials in a variety of solar cell systems such as organic solar cells, perovskite solar cells, and dye‐sensitized solar cells, especially some metals to improve the photoelectric performance of the device as dopants. In the end, perspectives on the opportunities and challenges of OMCs are given.

While the scientific research value, economic value and social value of research data have become increasingly apparent, the significance of open research data has reached a consensus. This article gives an introduction to open research data policies and measures in China, and reports on the status of constructing necessary infrastructure, specifically open data repositories. We compare open data repositories in China and Western countries in terms of scale, subject distribution, data policies, service and content operations. In addition, this article summarizes methods and motivations for data sharing among researchers in China. Finally, the paper discusses the characteristics, potential problems and challenges of China's open research data practices. We conclude with some suggestions for the future development of open research data in China from data policy, infrastructure construction, compliance with international standards and norms, credibility and influence improvement, incentives for data sharing and encouraging data sharing research practices.