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The single‐atom Fe−N−C catalyst has shown great promise for the oxygen reduction reaction (ORR), yet the intrinsic activity is not satisfactory. There is a pressing need to gain a deeper understanding of the charge configuration of the Fe−N−C catalyst and to develop rational modulation strategies. Herein, we have prepared a single‐atom Fe catalyst with the co‐coordination of N and O (denoted as Fe−N/O−C) and adjacent defect, proposing a strategy to optimize the d‐orbital spin‐electron filling of Fe sites by fine‐tuning the first coordination shell. The Fe−N/O−C exhibits significantly better ORR activity compared to its Fe−N−C counterpart and commercial Pt/C, with a much more positive half‐wave potential (0.927 V) and higher kinetic current density. Moreover, using the Fe−N/O−C catalyst, the Zn‐air battery and proton exchange membrane fuel cell achieve peak power densities of up to 490 and 1179 mW cm−2, respectively. Theoretical studies and in situ electrochemical Raman spectroscopy reveal that Fe−N/O−C undergoes charge redistribution and negative shifting of the d‐band center compared to Fe−N−C, thus optimizing the adsorption free energy of ORR intermediates. This work demonstrates the feasibility of introducing an asymmetric first coordination shell for single‐atom catalysts and provides a new optimization direction for their practical application. [ABSTRACT FROM AUTHOR]

The aerosol deposition process, involving the impact of solid particles on a substrate at high velocities, is an attractive method for the manufacture of ceramic coatings at room temperature. For process optimisation, it is crucial to select a powder having the appropriate physical characteristics and evaluate the particle flow behaviour during the deposition process. In this study, a powder modification process using high-energy milling and spray drying to improve the applicability of precursor powders was developed and evaluated both numerically and experimentally. A modified aerosol deposition system incorporating a brush-type aerosol generator was employed to maintain the continuity of the aerosol supply and improve the stability of the particle concentration. The deposition efficiency was nearly tripled when using spray-dried granules (0.68%) instead of the as-received powders (0.26%). From tribological measurements, the strongest interfacial bonding was also confirmed for coatings prepared with alumina granules. [ABSTRACT FROM AUTHOR]

Quenching procedures are effective in enhancing the low depolarization temperature of sodium bismuth titanate (NBT) relaxor ferroelectrics. In the present work, the influence of thermal processing parameters on the structure and electrical properties of NBT ceramics modified with 5 mol% sodium niobate (NBT-5NN) are evaluated. It is shown that quenching leads to higher electrical conductivity due to reduction at high temperatures, resulting in a higher oxygen vacancy concentration. The quenched materials also exhibit enhanced rhombohedral distortion and ferroelectric properties. The reduction process is largely reversible by reoxidation during annealing at intermediate temperatures in the region of 550 °C, which helps to recover the bulk resistivity to values close to those of the as-sintered materials. On the other hand, the rhombohedral distortion and ferroelectric properties were not affected significantly by the annealing procedure, indicating that the mechanisms responsible for the modification of electrical conductivity and structural distortion/ferroelectric properties have a different origin. [ABSTRACT FROM AUTHOR]

Highlights: The advancement and current status of dual-atom catalysts are reported. The synergistic effects exhibited by recent dual-atom catalysts in mechanistic studies are classified and summarized. Challenges and prospects of dual-atom catalysts in synthesis, characterization, applications, and theory are discussed. The exploration of sustainable energy utilization requires the implementation of advanced electrochemical devices for efficient energy conversion and storage, which are enabled by the usage of cost-effective, high-performance electrocatalysts. Currently, heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of applications. Compared to conventional catalysts, atomically dispersed metal atoms in carbon-based catalysts have more unsaturated coordination sites, quantum size effect, and strong metal–support interactions, resulting in exceptional catalytic activity. Of these, dual-atomic catalysts (DACs) have attracted extensive attention due to the additional synergistic effect between two adjacent metal atoms. DACs have the advantages of full active site exposure, high selectivity, theoretical 100% atom utilization, and the ability to break the scaling relationship of adsorption free energy on active sites. In this review, we summarize recent research advancement of DACs, which includes (1) the comprehensive understanding of the synergy between atomic pairs; (2) the synthesis of DACs; (3) characterization methods, especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy; and (4) electrochemical energy-related applications. The last part focuses on great potential for the electrochemical catalysis of energy-related small molecules, such as oxygen reduction reaction, CO2 reduction reaction, hydrogen evolution reaction, and N2 reduction reaction. The future research challenges and opportunities are also raised in prospective section. [ABSTRACT FROM AUTHOR]

The membrane electrode assembly (MEA) is a critical part of proton exchange membrane fuel cells (PEMFCs) and has a significant impact on their performance. A novel preparation method of MEA is proposed in this work to inhibit the swelling and deformation of the proton exchange membrane (PEM) during MEA preparation and improve the interface between the PEM and cathode catalyst layer (CL). Using this novel fabrication method, an asymmetric MEA is prepared, where the anode and cathode parts are fabricated separately and then integrated by a hot-pressing process. The cathode part is prepared by covering the gas diffusion electrode (GDE) onto a layer of a perfluorosulfonic acid dispersion to form a membrane-coated electrode according to a wet-contact interface design, thereby ensuring a tight and concave-convex PEM/CL interface on the cathode. The anode part is prepared by spraying the CL onto a commercial PEM with a substrate to form a CL-coated PEM. An MEA was also prepared according to the traditional catalyst-coated membrane (CCM) method for comparison. The asymmetric MEA based on the new manufacturing process performs better than the traditional CCM-type MEA under the same PEM thickness prerequisite. The peak power densities of the asymmetric MEA are verified to be 18% (H 2 /air) and 31% (H 2 /O 2) higher than conventional CCM-type MEA. In addition, the asymmetric MEA shows less cell performance degradation after 3000 dry/wet test cycles than the CCM-type MEA. • An asymmetric membrane electrode assembly is produced. • The cathode part is prepared according to a wet-contact interface design. • The anode part is prepared by spraying the CL onto a commercial PEM. • The asymmetric MEA performs better than the traditional CCM-type MEA. [ABSTRACT FROM AUTHOR]

Membrane electrode assemblies (MEAs) are critical components in influencing the electrochemical performance of high-temperature proton exchange membrane fuel cells (HT-PEMFCs). MEA manufacturing processes are mainly divided into the catalyst-coated membrane (CCM) and the catalyst-coated substrate (CCS) methods. For conventional HT-PEMFCs based on phosphoric acid-doped polybenzimidazole (PBI) membranes, the wetting surface and extreme swelling of the PA-doped PBI membranes make the CCM method difficult to apply to the fabrication of MEAs. In this study, by taking advantage of the dry surface and low swelling of a CsH5(PO4)2-doped PBI membrane, an MEA fabricated by the CCM method was compared with an MEA made by the CCS method. Under each temperature condition, the peak power density of the CCM-MEA was higher than that of the CCS-MEA. Furthermore, under humidified gas conditions, an enhancement in the peak power densities was observed for both MEAs, which was attributed to the increase in the conductivity of the electrolyte membrane. The CCM-MEA exhibited a peak power density of 647 mW cm−2 at 200 °C, which was ~16% higher than that of the CCS-MEA. Electrochemical impedance spectroscopy results showed that the CCM-MEA had lower ohmic resistance, which implied that it had better contact between the membrane and catalyst layer. [ABSTRACT FROM AUTHOR]

Herein, the photoresponse performance of g-C 3 N 4 films with high crystallinity has been investigated under high pressure for the first time. It is found that the photocurrents are enhanced with increasing pressure, achieving 1.8 times increase at a mild pressure of approximately 3.6 GPa in comparison with the initial value. Theoretical calculation suggests that the photocurrent changes are mainly related to the bandgap reduction due to the increased interlayer interactions under compression. Our findings provide new insights into the control of the photoelectric performance of g-C 3 N 4 materials by pressure engineering, and may promote the development of the pressure-controlled optoelectronic devices applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The structure and properties of Mn‐doped 0.67BiFeO3‐0.33BaTiO3 ceramics are systematically investigated with respect to the effects of annealing prior to rapid cooling by quenching in air. Air‐quenching induces a change in crystal structure from pseudo‐cubic to rhombohedral, with higher quenching temperatures leading to an increased rhombohedral distortion. These structural changes are correlated with the appearance of more well‐defined ferroelectric domain configurations. It is shown that the surface preparation procedures for XRD measurements can induce significant changes in the peak profiles, indicating differences in crystal structure between the surface and bulk regions. Frequency dispersion in the temperature‐dependent relative permittivity for the as‐sintered sample is significantly reduced after quenching, accompanied by enhancement of the Curie point and improved temperature‐stability of piezoelectric properties. It is proposed that the formation of defect clusters by A‐site cation diffusion during cooling is circumvented by quenching, leading to the observed modification of structural distortion and ferroelectric properties. [ABSTRACT FROM AUTHOR]

• Domain switching and lattice strain in polycrystalline K 0.5 Bi 0.5 TiO 3 -BiFeO 3 -PbTiO 3 is evaluated by in-situ high energy synchrotron XRD. • The tetragonal {200} grain family exhibited the highest effective lattice strain up to 8.2 × 10−3 at an electric field of 5 kV/mm. • A partial phase transformation from tetragonal to rhombohedral occurred at high electric field levels, with an average strain of −1.54 × 10−3. • Relaxation of intergranular stress gives rise to enhanced domain switching in KBT-BF-PT ceramics. • The observed self-adapting mechanism could also be exploited in other high performance, high temperature piezoelectric ceramics. We report an in-situ synchrotron X-ray diffraction study of K 0.5 Bi 0.5 TiO 3 -BiFeO 3 -PbTiO 3 ceramics, which exhibit a T c of around 450 °C. The electromechanical actuation mechanisms comprise contributions from coexisting tetragonal and rhombohedral phases. The tetragonal {200} grain family exhibited the highest effective lattice strain, up to 8.2 × 10−3 at 5 kV/mm. Strong strain anisotropy in the tetragonal phase and field-induced intergranular stresses facilitate a partial transformation from tetragonal (high strain anisotropy) to rhombohedral (low strain anisotropy) at high electric field levels, with an average linear transformation strain of -1.54 × 10-3. The domain switching behavior was effectively enhanced in both tetragonal and rhombohedral phases after the phase transformation, due to the release of intergranular stress. This observed self-adapting mechanism in tuning intergranular stress through partial phase switching in the morphotropic KBT-BF-PT composition with large lattice distortion could also be exploited in other perovskite systems in order to achieve high performance high temperature piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Pyriproxyfen is a juvenile hormone analogue. The physiological effects of its low-concentration drift during the process of controlling agricultural and forestry pests on non-target organisms in the ecological environment are unpredictable, especially the effects on organs that play a key role in biological function are worthy of attention. The silk gland is an important organ for silk-secreting insects. Herein, we studied the effects of trace pyriproxyfen on autophagy and apoptosis of the silk gland in the lepidopteran model insect, Bombyx mori (silkworm). After treating fifth instar silkworm larvae with pyriproxyfen for 24 h, we found significant shrinkage, vacuolization, and fragmentation in the posterior silk gland (PSG). In addition, the results of autophagy-related genes of ATG8 and TUNEL assay also demonstrated that autophagy and apoptosis in the PSG of the silkworm was induced by pyriproxyfen. RNA-Seq results showed that pyriproxyfen treatment resulted in the activation of juvenile hormone signaling pathway genes and inhibition of 20-hydroxyecdysone (20E) signaling pathway genes. Among the 1808 significantly differentially expressed genes, 796 were upregulated and 1012 were downregulated. Among them, 30 genes were identified for autophagy-related signaling pathways, such as NOD-like receptor signaling pathway and mTOR signaling pathway, and 30 genes were identified for apoptosis-related signaling pathways, such as P53 signaling pathway and TNF signaling pathway. Further qRT-PCR and in vitro gland culture studies showed that the autophagy-related genes Atg5, Atg6, Atg12, Atg16 and the apoptosis-related genes Aif, Dronc, Dredd, and Caspase1 were responsive to the treatment of pyriproxyfen, with transcription levels up-regulated from 24 to 72 h. In addition, ATG5, ATG6 , and Dronc genes had a more direct response to pyriproxyfen treatment. These results suggested that pyriproxyfen treatment could disrupt the hormone regulation in silkworms, promoting autophagy and apoptosis in the PSG. This study provides more evidence for the research on the damage of juvenile hormone analogues to non-target organisms or organs in the environment, and provides reference information for the scientific and rational use of juvenile hormone pesticides. [Display omitted] • • Pyriproxyfen promoted autophagy and apoptosis in silk glands of silkworm. • • Differentially transcribed genes related to autophagy and apoptosis of silkworm silk gland induced by pyriproxyfen were obtained. • • In vitro culture verified the role of ATG5, ATG6 genes in promoting autophagy of silkworm silk gland. • • In vitro culture verified the role of Dronc genes in promoting apoptosis of silkworm silk gland. [ABSTRACT FROM AUTHOR]

Fe3O4 nanoparticle-encapsulating N-doped porous carbon was synthesized. Owing to the large specific surface area, hierarchical porous structure, and sufficient number of active sites from the graphitic carbon wrapped Fe3O4 NPs as well as the joint effect with Fe–Nx moieties, the as-prepared 2D-Fe3O4@FeNC-700 electrocatalyst exhibits exceptional performance in Zn–air batteries. [ABSTRACT FROM AUTHOR]

Cytoskeleton has been reported to play an essential role in facilitating the viral life cycle. However, whether the host can exert its antiviral effects by modulating the cytoskeleton is not fully understood. In this study, we identified that host factor DUSP5 was upregulated after dengue virus (DENV) infection. In addition, we demonstrated that overexpression of DUSP5 remarkably inhibited DENV replication. Conversely, the depletion of DUSP5 led to an increase in viral replication. Moreover, DUSP5 was found to restrain viral entry into host cells by suppressing F-actin rearrangement via negatively regulating the ERK-MLCK-Myosin IIB signaling axis. Depletion of dephosphorylase activity of DUSP5 abolished its above inhibitory effects. Furthermore, we also revealed that DUSP5 exhibited broad-spectrum antiviral effects against DENV and Zika virus. Taken together, our studies identified DUSP5 as a key host defense factor against viral infection and uncovered an intriguing mechanism by which the host exerts its antiviral effects through targeting cytoskeleton rearrangement. • DUSP5 retrains viral entry into host cells by suppressing F-actin rearrangement. • DUSP5 negatively regulates the ERK-MLCK-Myosin IIB signaling axis. • DUSP5 exhibits broad-spectrum antiviral effects against dengue virus and Zika virus. [ABSTRACT FROM AUTHOR]

Abstract In the present study, we report a nonergodic relaxor ferroelectric composition for high temperature piezoelectric applications, 0.57BiFeO 3 -0.21K 0.5 Bi 0.5 TiO 3 -0.22PbTiO 3 , which exhibits T m around 420 °C. By combining the results of in-situ synchrotron XRD and strain measurements using digital image correlation, a pseudocubic nonergodic relaxor to rhombohedral ferroelectric transformation is identified, accompanied by a volume strain close to zero. A methodology is developed to determine the crystallographic parameters of the transformed rhombohedral ferroelectric phase in a strain-free state, using the invariant intersection for diffraction stress analysis. The phase transformation process was analyzed by methods combining peak profile fitting and full pattern refinement; the results obtained illustrate the strain arising from the phase transformation, together with intrinsic/extrinsic contributions and anisotropy in the field-induced strain. The study reveals unusual microscopic strain behavior, distinguished from that of normal rhombohedral ferroelectrics, showing the combined properties of ergodic and normal ferroelectric materials and leading to a dominant intrinsic lattice strain together with a weaker extrinsic domain switching effect. The elastic coupling between different grain families is also reflected in their similar strain orientation distribution (SOD) functions. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract A coherent core-shell structure in 0.24BiFeO 3 -0.56K 0.5 Bi 0.5 TiO 3 -0.20PbTiO 3 ceramics, with T m around 385 °C, was revealed using a combination of characterisation methods including scanning and transmission electron microscopy. The core regions consist of a cubic matrix with minor monoclinic phase with limited coherence length, while the shell regions are a tetragonal phase with characteristic long-range ordered ferroelectric domain structures. The electric field-induced strains for both core and shell regions were investigated by conducting an in-situ poling study using high energy synchrotron X-ray diffraction (XRD). A methodology is developed to evaluate both intrinsic (lattice strain) and extrinsic (domain switching) contributions for each phase based on diffraction peak profile fitting for multiple reflections. It is shown that there were no significant variations in the cubic and tetragonal phase fractions under an electric field in the range from −6 to +6 kV mm−1. An irreversible strain ∼0.04% was attributed mainly to ferroelectric domain switching in the tetragonal shell regions, while a reversible lattice strain ∼0.12% was identified in the pseudo-cubic core, leading to significant levels of intra-granular stress. Strain anisotropy, dependent on the crystallographic orientation of different grain families, was also evident. Macroscopic strain measurements, conducted using a novel digital image correlation (DIC) method, demonstrated the formation of typical 'butterfly'-type strain-electric field loops and were consistent with the total strain values calculated from the XRD results. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

In the study, hydrogen effects on the fracture toughness of an API X90 pipeline steel are investigated considering specimen thickness effects. It is found that the embrittlement of fracture increases with thickness for the hydrogenated specimens. The fracture toughness of hydrogen-free specimens are about 2.9, 5.2 and 11.6 times larger than the hydrogenated ones for B / W = 0.5, 1 and 2, respectively. Digital image correlation (DIC) measurement indicates that as the specimen thickness increases, hydrogen deteriorates drastically the plasticity in the vicinity of the crack tip. A remarkably low dislocation density is observed, indicating hydrogen atom has great influence on the cohesive energy, rather than the dislocation pile-ups. Finally, it is concluded that hydrogen enhanced decohesion (HEDE) mechanism is responsible for the high hydrogen sensitivity to the specimen thickness. [ABSTRACT FROM AUTHOR]

[Display omitted] • Differences in the biochemical composition of seven types of tissues are analyzed. • A new one-dimensional convolutional hierarchical network (H-CNN) is proposed. • H-CNN classifies tissue samples in a hierarchy from coarse to fine. • H-CNN outperforms traditional classification models. Cervical cancer is one of the most common cancers with a long latent period and slow onset process. Early and accurate identification of the stage of cervical cancer can significantly improve the cure rate and patient survival time. In this study, we collected 699 Raman spectral data of tissue sections from 233 different patients. We analyzed and compared the characteristics and differences of the mean Raman spectra of the seven tissues and pointed out the main differences in the biochemical composition of the seven tissues. In this study, 1D hierarchical convolutional neural network (H-CNN) is proposed by integrating the prior knowledge of hierarchical classification relations with the research of deep learning in Raman spectroscopy. H-CNN is based on CNN and is added with three network branches. Hierarchical classification is performed from coarse to fine for tissue samples of cervicitis, Low-grade Squamous Cell Carcinoma, High-grade Squamous Cell Carcinoma, Well Differentiated Squamous Cell Carcinoma, Moderately Differentiated Squamous Cell Carcinoma, Poorly Differentiated Squamous Cell Carcinoma and cervical adenocarcinoma. To evaluate the recognition performance of H-CNN, we compared it with traditional methods such as Bayesian classifier (NB), decision tree classifier (DT), support vector machine classifier (SVM) and CNN. The experimental results show that H-CNN can accurately identify different classes of tissue sections and has apparent advantages in several aspects such as recognition accuracy, stability and sensitivity compared with the other four traditional recognition methods. The classification Macro-Accuracy of H-CNN can reach 94.91%, Macro-Recall can reach 95.31%, Macro-F1 can reach 95.23%, and Macro-AUC can reach 97.35%. The hierarchical classification method proposed in this study can diagnose patients more accurately. This could lay the foundation for further research on Raman spectroscopy as a clinical diagnostic method for cervical cancer. [ABSTRACT FROM AUTHOR]

Evidence concerning the individual differences in neutralizing antibody responses after receiving the COVID-19 vaccine remains lacking. In this study, we collected the serum and Peripheral blood mononuclear cells(PBMC) of 16 subjects who had never suffered from COVID-19 before during the course of two vaccine doses. Microneutralization assay is used to determine the immune response intensity of vaccine subjects. we revealed the change trend of TCR diversity using T cell receptor (TCR) sequencing. Then, we analyzed the correlation between HLA class II allele frequencies and the intensity of immune response. Finally, we identified several CDR3 sequences related to the intensity of the immune response. We analyzed the differences in D50 (DD50) between different time points, and found that there were two patterns in the change trend of TCR diversity, and the increased diversity group has stronger immune response. The inactivated vaccine is different from the mRNA vaccine against the spike protein, resulting in differences in TCR repertoire response patterns and antibody responses, which are related to HLA-DRB1 * 09:01. The presence of specific CDR3 sequences in the increased diversity group, rather than gene usage of the VJ gene, determines the intensity and persistence of neutralizing antibody titers. Finally, We identified the different response patterns of the human TCR repertoire to inactivated vaccines. The pattern with increased diversity is more likely to appear strong and more lasting immune response. • This article focuses on vaccine injection subjects who have never been infected with COVID-19. • The correlation between immune response and TCR was longitudinal observed at different time points. • HLA-DRB1*09:01 was found to be related to the intensity of immune response. • TCR clonotypes related to immune response intensity were screened out. [ABSTRACT FROM AUTHOR]

A kinetic model based on the elementary reaction velocity theory is useful for investigating the kinetic rules of chemical reactions under subcritical and supercritical conditions. This model can be used to determine the stochastic relations between the hydrolysis products and conversion time in subcritical water based on the molecular collision theory. First, hydrolysis reaction experiments using rapeseed oil were conducted, and the collected data were used to verify the effectiveness of this stochastic kinetic model. The results showed that the kurtosis of this model was 1.11922, skewness was −1.49277 and mean error of the system was 0.81499, which was relatively small. Meanwhile, the adjustment coefficient (Adj. R 2 ) was 0.98923, which indicated that this model is highly significant, that is, it can accurately depict the microscopic stochastic process of the rapeseed oil hydrolysis reaction. Furthermore, it verifies that the stochastic theory and molecular collision theory are feasible under subcritical conditions, which is a breakthrough in the field of the kinetic study of high-temperature and high-pressure reaction systems. Furthermore, the model reveals the changing rules of the reaction order and reaction velocity of the rapeseed oil hydrolysis reaction, which provides an important reference for parameter optimization of industrial reactor design. [ABSTRACT FROM AUTHOR]

In the study, the experiments are performed to determine thickness effect on critical crack tip opening displacement ( δ IC ) of the single-edge tension (SE(T)) specimen with side-groove. The applicability and thickness sensitivity of several fracture toughness estimation procedures are also investigated by the experimental data. Referring to the results by the double clip gauge method, it is found that the critical crack initiation toughness decreases significantly as specimen thickness increases until the thickness-to-width ratio equal to 4, beyond which thickness effect becomes relatively weak. Accordingly, a dimension size is recommended for the fracture toughness testing to take the out-of-plane constraint into account for SE(T) specimen. The further analyses based on the plastic zone size confirm the result as well. [ABSTRACT FROM AUTHOR]

The structures and functional properties of Na0.5Bi0.5TiO3- xKNbO3 (NBT-xKN) solid solutions, with x in the range from 0.01 to 0.09, were investigated using a combination of high-resolution synchrotron X-ray powder diffraction (SXPD) and ferroelectric property measurements. For low KN contents, an irreversible transformation from cubic to rhombohedral phases was observed after the application of a high electric field, indicating that the polar nanoregions (PNRs) in the unpoled state can be transformed into metastable long-range ordered ferroelectric domains in the poled state. In contrast, the near-cubic phase of the unpoled ceramics was found to be remarkably stable and was retained on cooling to a temperature of −175°C. Upon heating, the field-induced metastable ferroelectric rhombohedral phase transformed back to the nanopolar cubic state at the structural transformation temperature, TST, which was determined as approximately 225°C and 125°C for KN contents of 3% and 5% respectively. For the field-induced rhombohedral phase in the poled specimens, the pseudo-cubic lattice parameter, ap, exhibited an anomalous reduction while the inter-axial angle increased towards a value of 90° on heating, resulting in an overall increase in volume. The observed structural changes were correlated with the results of temperature-dependent dielectric, ferroelectric and depolarization measurements, enabling the construction of a phase diagram to define the stable regions of the different ferroelectric phases as a function of composition and temperature. [ABSTRACT FROM AUTHOR]

Ferroptosis, first proposed in 2012, is an iron-dependent form of regulated cell death characterized by excessive polyunsaturated fatty acid oxidation. In the past decade, researchers have revealed the formation and mechanisms of ferroptosis. Cancer drug resistance can be reversed by ferroptosis induction, and inhibiting ferroptosis has been shown to block certain disease processes. As a result, several ferroptosis-targeting drugs have been developed. However, the first-generation ferroptosis-targeting agents remain hampered from clinical use, mainly due to poor selectivity and pharmacokinetics. The discoveries of FSP1, GCH1, and other potential ferroptosis-regulating pathways independent of Xc−-GSH-GPX4 provide novel targets for drug design. Recently, protein-targeted degradation and antibody-drug conjugate strategy show promise in future drug design. With novel targets, further optimizations, and new technologies, the next-generation ferroptosis-targeting agents show a promising future with improved selectivity and efficacy. In this review, we summarize mechanisms, target types, drug design, and novel technologies of ferroptosis, aiming to pave the way for future drug design and discovery in the next decade. [Display omitted] • Summarize drug design and discovery in ferroptosis comprehensively. • Summarize the latest progress in target types of ferroptosis. • Introduce new technologies in ferroptosis drug design. • Propose appliable suggestions for further development. [ABSTRACT FROM AUTHOR]

The Internet has become an important source of health information for elderly people in China. A controlled user experiment was conducted to understand how Chinese elderly people search for online health information. Twenty elderly people completed three search tasks based on three different health information seeking contexts. Online health information seeking behavior patterns of the elderly were found to include reselecting from results pages, following hyperlinks, and using a query reformulation patter. There was no significant difference with respect to emotion and the three task contexts, as elderly people have positive attitudes regarding the health information seeking process, but cognition within the three task contexts displayed significant differences. There was a significant correlation between education and Internet search proficiency regarding task search performance, while health condition, familiarity with the Internet and credibility of online health information were found to be primary factors that influenced the decision of the elderly to search for online health information. [ABSTRACT FROM AUTHOR]

FeCl3-catalyzed aza-Diels-Alder reaction of methylenecyclopropane with imine provides a facile and efficient route for the synthesis of tetrahydroquinoline with a spirocyclopropyl ring. [ABSTRACT FROM AUTHOR]

BiFeO3–BaTiO3 (BF–BT) ceramics exhibit great potential for diverse applications in high temperature piezoelectric transducers, temperature-stable dielectrics and pulsed-power capacitors. Further optimization of functional properties for different types of applications can be achieved by modification of processing parameters or chemical composition. In the present work, the influence of pentavalent niobium substitution for trivalent ferric ions on the structure, microstructure and dielectric properties of 0.7BF–0.3BT ceramics was investigated systematically. Doping with niobium led to incremental reductions in grain size (from 7.0 to 1.3 µm) and suppression of long-range ferroelectric ordering. It was found that core-shell type microstructural features became more prominent as the Nb concentration increased, which were correlated with the formation of distinct peaks in the dielectric permittivity–temperature relationship, at ~470 and 600 °C, which were attributed to the BT-rich shell and BF-rich core regions, respectively. Nb-doping of BF–BT ceramics yielded reduced electronic conductivity and dielectric loss, improved electrical breakdown strength and enhanced dielectric energy storage characteristics. These effects are attributed to the charge compensation of pentavalent Nb donor defects by bismuth vacancies, which suppresses the formation of oxygen vacancies and the associated electron hole conduction mechanism. The relatively high recoverable energy density (Wrec = 2.01 J cm−3) and energy storage efficiency (η = 68%) of the 0.7BiFeO3–0.3BaTiO3 binary system were achieved at 75 °C under an electric field of 15 kV mm−1. This material demonstrates the greatest potential for applications in energy storage capacitors and temperature-stable dielectrics. [ABSTRACT FROM AUTHOR]

• An improved J estimation method is proposed for circumferentially surface cracked pipes subjected to reeling. • A geometry and material dependent parameter is introduced to relate the reference stress to the uncracked remote stress. • The proposed limit load solution has an explicitly theoretical foundation and is capable to provide conservative estimation of J -integral for geometries over the full range of interest. In the study, an improved reference load solution is proposed to determine the reference stress and the J -integral for pipelines subjected to reeling, where the axial strains during installation are typically within the range of 1.5%–3.5%. Accordingly, the reference stress can be directly correlated with the un-cracked remote stress of the component through the loading-independent parameter, λ. The effects of cracked geometries and material properties on the reference stress are systematically investigated, and an empirical formula for the reference stress is provided. The proposed method is validated against various J estimation schemes in the literature. It is concluded that the present reference load solution is able to provide an improved and simplified J -integral estimation for the considered geometries over the full strain range of interest. [ABSTRACT FROM AUTHOR]

The spatter generated by the interaction between laser and powder during Powder Bed Fusion-Laser Melting (PBF-LM) can significantly affect the quality of printed parts. A high-speed camera is used to observe the dynamic process of spatter's behavior under different layer thickness and laser powers during the printing process, and to analyze the printed samples' surface roughness, microstructure, and mechanical properties. In terms of spatter image processing, employing an optical flow approach to track and quantify the number of spatters efficiently eliminates statistical redundancy and improves statistical correctness. It is found that under the same laser power, the number of spatters produced by the laser scan direction with the gas flow (LSD-W) is more than that by the laser scan direction against the gas flow (LSD-A), and the number of spatters produced increases with the increase of laser power. Analyzing the mechanical properties and surface roughness of the printed samples under different process parameters quantitatively reveals that differences in the spatter amount generated under different process parameters in the PBF-LM process is not the determining factor affecting the difference in tensile strength of printed parts. During LSD-W, the number of spatters generated at laser power of 170 W and layer thickness of 0.03 mm is 87, and the tensile strength of the printed sample is 618 MPa. During LSD-W, the number of spatters generated at laser power of 320 W and layer thickness of 0.05 mm is 211, and the tensile strength of the printed sample is 680 MPa. Instead, spatter generation has a more direct impact on the surface roughness of printed parts. The layer thickness is 0.03 mm, the laser power is 170 W, and (Ra = 2.372 μm) is the surface roughness of the sample. The layer thickness is 0.05 mm, the laser power is 320 W, and (Ra = 8.163 μm) is the surface roughness of the sample. [ABSTRACT FROM AUTHOR]

Previous studies on the cut quality of sugarcane stalks have mainly focused on external factors. However, the effects of internal factors on the cut quality have rarely been studied. In this study, the influence of internal and external factors on the cut quality were considered. Numerical finite element simulations and an experimental design were utilised to investigate the influences of the internal and external factors on the cut quality. The numerical model was validated using experimental cutting tests and based on a theoretical analysis. The optimum combination of cutting system parameters was investigated using an orthogonal test. The cut quality of the optimal combination was verified based on experiments. From the results, it was seen that the cutting bevel angle plays a significant role in affecting the cutting force, whereas machine forward speed (within the range 0.4–0.6 m s−1) and rotational speed (within the range 650–750 rpm) had no noticeable influence on cutting force. The optimal combination obtained by the orthogonal experiment was a cutting bevel angle of 30°, forward speed of 0.4 m s−1, and cutter rotational speed of 650 rpm. The optimised parameter combination produced an improved quality of cut in a cutting test. The damage mechanisms of sugarcane arising from internal factors were also investigated. This study provides basic information for the design of a base cutter for sugarcane harvesting. • Internal and external cut quality factors examined by simulation and experiment. • Finite element numerical simulations verified by real cutting test. • Optimum settings determined by orthogonal experiment and verified by test. • Lower cutting forces benefit good quality cutting. • Damage mechanism of stem explained by numerical simulations. [ABSTRACT FROM AUTHOR]

• Human metapneumovirus (HMPV) is an important respiratory pathogen that causes acute respiratory tract infection in children ≤5 years old. • The prevalence peak of HMPV in southern China appeared between March and May. • Respiratory syncytial virus is the most common respiratory virus coinfected with HMPV in children. • The predominant subtype of HMPV in this area is B1, followed by A2c subtype. • Long sunshine duration might decrease the HMPV prevalence. This study aimed to determine the epidemiological and genetic features of human metapneumovirus (HMPV) infection in children in southern China, and the effect of meteorological factors on infection. 14,817 children (≤14 years) with acute respiratory tract infections from 2010 to 2019 were examined for HMPV and other respiratory viruses by real-time quantitative polymerase chain reaction. Full-length F gene of 54 positive samples were sequenced and subjected to phylogenetic analysis. The correlation between the HMPV-positive rate and meteorological factors was analyzed by linear regression analysis. HMPV was detected in 524 (3.5%) children, who were mostly younger than 1 year. The seasonal peak of HMPV prevalence mainly occurred in spring. Respiratory syncytial virus was the most common virus coinfected with HMPV (5.3%). Phylogenetic analysis revealed that the sequenced HMPV strains belonged to four sublineages, including A2b (1.9%), A2c (31.5%), B1 (50.0%), and B2 (16.7%). After adjusting for all meteorological factors, sunshine duration was inversely correlated with the HMPV-positive rate. HMPV is an important respiratory pathogen that causes acute respiratory tract infections in children in southern China, particularly in children ≤5 years old. The prevalence peak of HMPV in this area appeared in spring, and the predominant subtype was B1. Meteorological factors, especially long sunshine duration, might decrease the HMPV prevalence. [ABSTRACT FROM AUTHOR]

Aerosol deposition is a feasible method of fabricating dense ceramic films at room temperature by the impact consolidation of submicron‐sized particles on ceramic, metal, glass, and polymer substrates at a rapid rate. Despite the potential usefulness of the aerosol deposition process, there are issues, such as deposition mechanisms and structure of the film‐substrate interface, that are not well understood. We have used complementary structural and microstructural analysis to capture the state of the substrate surface after the aerosol deposition process. The results reveal that modification of the substrate surface by the ejected submicron‐sized particles is essential for the formation of anchoring layer, thereby, a change in internal residual stress state and surface free energy of the substrate is required to deposit film using AD process. Our analysis also suggests that the adhesion between the metal substrate and ceramic particles is possibly contributed by both physical bonding and mechanical interlocking. [ABSTRACT FROM AUTHOR]

An unfilled tungsten bronze-structured ferroelectric ceramic, Ca 0.28 Ba 0.72 Nb 2 O 6 (CBN28), has been doped with Y3+ to produce ceramics with a nominal composition, (Ca 0.28 Ba 0.72) 1–3w/2 Y w Nb 2 O 6 [0 ≤ w ≤ 0.05]. The substitution of Y3+ for Ca2+/Ba2+, and consequent additional vacancy formation, is assumed to occur on the A1/A2 sites. This resulted in a minor reduction of the c lattice parameter, and unit cell volume. For undoped CBN28, there was a slightly diffuse relative permittivity-temperature (ε r -T) peak at 268 ⁰C. The peak became much broader for sample compositions w = 0.04 and 0.05 and the peak temperature showed a level of frequency dependence consistent with weak relaxor behaviour. The polarisation-electric field loops became narrower for samples w = 0.04 and 0.05, corresponding to a reduction in remnant polarisation value, from 2.4 to 0.8 µC cm−2 (30 kV cm−1). The Y doped ceramics exhibited stable relative permittivity over a wide temperature range, the variation being within± 15% of the median value from 36 ⁰C to 218 ⁰C for w = 0.05, when measured at 1 kHz. Consequently, we suggest that A site donor-doping and aliovalent B site doping of CBN holds potential for industry standard, temperature stable, high temperature dielectrics (ɛ r ≥ 500 ± 15% from - 55–250 + ⁰C). • Chemical modification (donor doping) of an unfilled Tungsten Bronze, Calcium Barium Niobate. • Temperature Stable Permittivity induced by Yttrium substitution and A-site vacancy addition. • Permittivity-Temperature response and Polarisation-Electric field loops suggest a transition to weak relaxor behaviour. [ABSTRACT FROM AUTHOR]

The estimation of fractional vegetation cover (FVC) is important for identifying and monitoring desertification, especially in arid and semiarid regions. By using regression and pixel dichotomy models, we present the comparison of Sentinel-2A (S2) multispectral instrument (MSI) and Landsat 8 (L8) operational land imager (OLI) data regarding the retrieval of FVC in a semi-arid sandy area (Mu Us Sandland, China, in August 2016). A combination of unmanned aerial vehicle (UAV) high-spatial-resolution images and field plots were used to produce verified data. Based on a normalized difference vegetation index (NDVI) regression model, the results showed that, compared with that of L8, the coefficient of determination (R2) of S2 increased by 26.0%, and the root mean square error (RMSE) and the sum of absolute error (SAE) decreased by 3.0% and 11.4%, respectively. For the ratio vegetation index (RVI) regression model, compared with that of L8, the R2 of S2 increased by 26.0%, and the RMSE and SAE decreased by 8.0% and 20.0%, respectively. When the pixel dichotomy model was used, compared with that of L8, the RMSE of S2 decreased by 21.3%, and the SAE decreased by 26.9%. Overall, S2 performed better than L8 in terms of FVC inversion. Additionally, in this paper, we develop a verified scheme based on UAV data in combination with the object-based classification method. This scheme is feasible and sufficiently robust for building relationships between field data and inversion results from satellite data. Further, the synergy of multi-source sensors (especially UAVs and satellites) is a potential effective way to estimate and evaluate regional ecological environmental parameters (FVC). [ABSTRACT FROM AUTHOR]

(1 − x)Na 0.5 Bi 0.5 TiO 3 -xKNbO 3 (NBT-xKN) ceramics, with x in the range 0.01–0.09, were prepared by solid state reaction and conventional sintering. A progressive transformation from a nano-polar to a long-range ordered ferroelectric phase was observed after the application of a cyclic electric field with an amplitude of 5 kV mm −1 . It is shown by analysis of the crushed ceramic pellets, using high resolution synchrotron x-ray diffraction, that the application the cyclic electric field induced an irreversible transformation from a pseudo-cubic nano-polar phase to a rhombohedral ordered ferroelectric phase having R3c symmetry. Furthermore, a systematic variation, from 89.6° to 90°, was observed in the rhombohedral interaxial angle as the KN content increased from 1 to 9%. By comparing the structural evidence with the ferroelectric polarization-electric field hysteresis loops, it is shown that the electric field-induced transformation is partially reversible for NBT-5KN and completely reversible or nonexistent for NBT-9KN. [ABSTRACT FROM AUTHOR]

High relative permittivity, ε r , over a very wide temperature range, −65 °C to 325 °C, is presented for ceramics designed to be compatible with base metal electrode multilayer capacitor manufacturing processes. We report a ≥ 300 °C potential Class II capacitor material, free from Bi or Pb ions, developed by doping Sr 2 NaNb 5 O 15 with Ca2+, Y3+ and Zr4+ ions, according to the formulation Sr 2−2z Ca z Y z NaNb 5-z Zr z O 15. For sample composition z = 0.025, ε r values are 1565 ± 15 % (1 kHz) from −65 °C to 325 °C. At a slightly higher level of doping, z = 0.05, ε r values are 1310 ± 10 % from −65 °C to 300 °C. Values of the dielectric loss tangent, tanδ are ≤ 0.025 from −60 °C to 290 °C, for z = 0.025, with tanδ increasing to 0.035 at 325 °C. Microstructural analyses exclude core-shell mechanisms being responsible for the flattening of the ε r –T response. [ABSTRACT FROM AUTHOR]

[Display omitted] • Without considering rainfall events, GHG emissions from urban rivers will be underestimated by 31%. • The CO 2 –equivalent emissions of GHG from urban rivers during a typhoon are 13.55 times higher than during fair weather. • Pumping drainage, sediment disturbance, and high gas transfer velocity are the primary factors behind GHG release during typhoons. Urban rivers have been recognized as significant hotspots for greenhouse gas (GHG) emissions. However, the impact of storms or typhoons on GHG emissions from urban rivers is not well understood. Suzhou Creek located in the highly developed urban area of Shanghai was selected to investigate of changes in CO 2 , CH 4 , and N 2 O concentrations and diffusive fluxes during different rainfall events from May to October 2021. The findings showed that urban rivers were sources of GHG emissions during various events. The average diffusive fluxes of CO 2 , CH 4 , and N 2 O during typhoon events were 1 to 2 orders of magnitude higher than those during non–typhoon period, revealing that typhoon greatly promote GHG evasion. GHG CO 2 –equivalents were ranked as follows: during typhoon (3.93 g m–2h−1) > post–typhoon (0.89 g m–2h−1) > high precipitation (0.33 g m–2h−1) > non–precipitation (0.29 g m–2h−1) > small precipitation (0.25 g m–2h−1). Rainfall dilution, pump station drainage, sediment disturbance, and a high gas transfer coefficient induced by typhoons were the main factors affecting GHG emissions. Nutrients, chlorophyll-a, and dissolved oxygen in river water were important control parameters for GHG production. Overall, typhoon would release large amounts of GHG from urban rivers. Given the projected increase in the frequency and complexity of extreme weather events, this study highlights the importance of better understanding the dynamic response of urban river GHG to rainfall and typhoons. [ABSTRACT FROM AUTHOR]

2D MXenes have attracted wide attention due to their unique chemical and physical properties. However, MXene nanosheets suffer from restacking and are susceptible to oxidation and consequently lose their functional properties which limits their applications. Thus, it is desirable to explore strategies to preserve MXene nanosheets and avoid oxidation. Herein, an effective strategy to produce MXene‐based conjugated microporous polymers (M‐CMPs) by covalently sandwiching MXene between CMPs using p‐iodophenyl functionalized MXene as templates is demonstrated. The as‐prepared M‐CMPs inherit the 2D architecture and high conductivity of MXene in terms of hierarchical porous structure and large specific surface area of CMPs. Moreover, the restacking and oxidation of MXene are simultaneously suppressed. Such advanced structural merits are critical for electrochemical energy storage. As‐proof‐of‐concept, the M‐CMPs are used as electrode materials for supercapacitors. As expected, with the improved structural advantages, M‐CMPs showcase superior capacitive performance than the MXene and CMPs counterparts. This work not only provides an opportunity for fabricating high performance MXene nanocomposites for energy storage/conversion but also has the potential to be generalized to resolve the challenges in the area of MXene engineering. [ABSTRACT FROM AUTHOR]

The focus of urban water environment renovation has shifted to high nitrate (NO 3 −) load. Nitrate input and nitrogen conversion are responsible for the continuous increase in nitrate levels in urban rivers. This study utilized nitrate stable isotopes (δ15N–NO 3 − and δ18O–NO 3 −) to investigate NO 3 − sources and transformation processes in Suzhou Creek, located in Shanghai. The results demonstrated that NO 3 − was the most common form of dissolved inorganic nitrogen (DIN), accounting for 66 ± 14% of total DIN with a mean value of 1.86 ± 0.85 mg L−1. The δ15N–NO 3 − and δ18O–NO 3 − values ranged from 5.72 to 12.42‰ (mean value: 8.38 ± 1.54‰) and −5.01 to 10.39‰ (mean value: 0.58 ± 1.76‰), respectively. Based on isotopic evidence, the river received a significant amount of nitrate through direct exogenous input and sewage ammonium nitrification, while nitrate removal (denitrification) was insignificant, resulting in nitrate accumulation. Analysis using the MixSIAR model revealed that treated wastewater (68.3 ± 9.7%), soil nitrogen (15.7 ± 4.8%) and nitrogen fertilizer (15.5 ± 4.9%) were the main sources of NO 3 − in rivers. Despite the fact that Shanghai's urban domestic sewage recovery rate has reached 92%, reducing nitrate concentrations in treated wastewater is crucial for addressing nitrogen pollution in urban rivers. Additional efforts are needed to upgrade urban sewage treatment during low flow periods and/or in the main stream, and to control non-point sources of nitrate, such as soil nitrogen and nitrogen fertilizer, during high flow periods and/or tributaries. This research provides insights into NO 3 − sources and transformations, and serves as a scientific basis for controlling NO 3 − in urban rivers. • Urban rivers have received significant amounts of nitrate through direct exogenous input and ammonium nitrification from sewage. • A weak permanent nitrate removal mechanism results in the accumulation of nitrate. • The main source of nitrate pollution in urban rivers is mainly due to the substantial input of treated wastewater. [ABSTRACT FROM AUTHOR]

Abstract Distinctive structure-property relationships are revealed in the relaxor ferroelectric ceramic solid solution, (1-x)K 0.5 Bi 0.5 TiO 3 - xBiMg 0.5 Ti 0.5 O 3 : 0.02 < x < 0.08. The constructed phase diagram and results of in-situ synchrotron X-ray diffraction provide explanations for temperature and electric field dependent anomalies in dielectric, ferroelectric and electromechanical properties. At room temperature a mixed phase tetragonal and pseudocubic phase field occurs for compositions 0 > x ≤ 0.07. As temperature rises to ≥150 °C, the ferroelectric tetragonal relaxor phase changes to a pseudocubic ergodic relaxor phase; this change in length scale of polar order is responsible for an inflection in relative permittivity - temperature plots. The transition is reversed by a sufficient electric field, thereby explaining the constricted form of polarisation-electric field loops measured at >150 °C. It is also responsible for a change in slope of the strain-electric field (S-E) plots which are relatively linear in the ferroelectric regime i.e. at temperatures up to 150 °C, giving unipolar strains of 0.11% at 20 °C and 0.14% at 150 °C (50 kV/cm field). The additional contribution from the effect of the field-induced pseudocubic to tetragonal transition, generates strains of ∼0.2% at 185 °C. Unusual for a piezoelectric solid solution, the maximum strains and charge coefficients (d 33 = 150 pC/N, 20 °C) do not coincide with a morphotropic or polymorphic phase boundary. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Highlights • Failure location in hydrogen embrittled stainless steel joint depends on pre-strain. • Severe strain-induced α′ martensite in the base metal contributes to failure mechanism transition. • Tendency of strain-induced α′ martensitic transformation for the weld metal and base metal is strongly determined by local chemical homogeneity. Abstract The effects of pre-strain on hydrogen embrittlement of 304L K-TIG welded joint were investigated. As pre-strain of joint increased, fracture location of hydrogen-charged joint changed from weld metal to base metal. In low prestrained joints, fracture may be initiated at the sites of clustered dislocations due to hydrogen in weld metal with a high density of pre-existing dislocations. In high prestrained joints, some regions in base metal suffered severe strain-induced α′ martensitic transformation due to Ni depletion bands and cracking occurred at phase boundaries where may provide more sites for the accumulation of hydrogen atoms and dislocations. [ABSTRACT FROM AUTHOR]

Abstract The effects of hydrogen on the mechanical properties of 304L keyhole tungsten inert gas welded joint were investigated in the study. The presence of hydrogen resulted in a significant decrease in the macroscopic ductility of the weld metal, and fracture may be initiated at the sites of clustered dislocations due to hydrogen atoms. Moreover, it is found that hydrogen may result in more severe loss in ductility and noticeable decrease in the flow stress and strength of the base metal, because of the interplay between the hydrogen atoms and strain-induced α′ martensite. Strain-induced α′ martensitic transformation and phase boundaries in the base metal may provide more sites for the accumulation of hydrogen and dislocations, leading to an appreciable decrease in the ductility and strength of the base metal. [ABSTRACT FROM AUTHOR]

Plant litter input is an important driver of soil/sediment organic carbon (SOC) turnover. A large number of studies have targeted litter-derived C input tracing at a global level. However, little is known about how litter carbon (C) input via various plant tissues affects SOC accumulation and mineralization. Here, we conducted laboratory incubation to investigate the effects of leaf litter and stem litter input on SOC dynamics using the natural 13C isotope technique. A 122-day laboratory incubation period showed that litter input facilitated SOC accumulation. Leaf and stem litter inputs increased soil total organic carbon content by 37.6% and 15.5%, respectively. Leaf litter input had a higher contribution to SOC accumulation than stem litter input. Throughout the incubation period, the δ13C values of stem litter and leaf litter increased by 1.5‰ and 3.3‰, respectively, while δ13CO 2 derived from stem litter and δ13CO 2 derived from leaf litter decreased by 4.2‰ and 6.1‰, respectively, suggesting that the magnitude of δ13C in litter and δ13CO 2 shifts varied, depending on litter tissues. The cumulative CO 2 –C emissions of leaf litter input treatments were 27.56%–42.47% higher than those of the stem litter input treatments, and thus leaf litter input promoted SOC mineralization more than stem litter input. Moreover, the proportion of increased CO 2 –C emissions to cumulative CO 2 –C emissions (57.18%–92.12%) was greater than the proportion of litter C input to total C (18.7%–36.8%), indicating that litter input could stimulate native SOC mineralization, which offsets litter-derived C in the soil. Overall, litter input caused a net increase in SOC accumulation, but it also accelerated the loss of native SOC. These findings provide a reliable basis for assessing SOC stability and net C sink capacity in wetlands. [Display omitted] • The effects of litter input from various plant tissues on SOC dynamics were studied. • Leaf litter input had a higher contribution to SOC storage than stem litter input. • The magnitude of δ13C in litter and δ13CO 2 shifts varied depending on litter tissues. • Leaf litter input promoted SOC mineralization more than stem litter input. • Litter input caused net increases in SOC storage, but it accelerated native SOC loss. [ABSTRACT FROM AUTHOR]

Vaccination is an effective strategy to fight COVID-19. However, the effectiveness of the vaccine varies among different populations in varying immune effects. Neutralizing antibody (NAb) level is an important indicator to evaluate the protective effect of immune response after vaccination. Lateral flow immunoassay (LFIA) is a rapid, safe and sensitivity detection method, which has great potential in the detection of SARS-CoV-2 NAb. In this study, a fluorescent beads-based lateral flow immunoassay (FBs-LFIA) and a latex beads-based LFIA (LBs-LFIA) using double antigen sandwich (DAS) strategy were established to detect NAbs in the serum of vaccinated people. The limit of detection (LoD) of the FBs-LFIA was 1.13 ng mL− 1 and the LBs-LFIA was 7.11 ng mL− 1. The two LFIAs were no cross-reactive with sera infected by other pathogenic bacteria. Furthermore, the two LFIAs showed a good performance in testing clinical samples. The sensitivity of FBs-LFIA and LBs-LFIA were 97.44% (95%CI: 93.15%–99.18%) and 98.29% (95%CI: 95.84%–99.37%), and the specificity were 98.28% (95%CI: 95.37%–99.45%) and 97.70% (95%CI: 94.82%–99.06%) compared with the conventional virus neutralization test (cVNT), respectively. Notably, the LBs-LFIA was also suitable for whole blood sample, requiring only 3 μL of whole blood, which provided the possibility to detect NAbs at home. To sum up, the two LFIAs based on double antigen sandwich established by us can rapidly, safely, sensitively and accurately detect SARS-CoV-2 NAb in human serum. [Display omitted] • LFIAs based on double antigen sandwich (DAS) have high sensitivity and specificity compared with cVNT. • The FBs-LFIA achieves a sensitivity of 97.44% and specificity of 98.28% in testing clinical serum samples (n = 389). • The LBs-LFIA achieves a sensitivity of 98.29% and a specificity of 97.70% in testing clinical serum samples (n = 554). • The LBs-LFIA can be used to plasma, serum and whole blood samples so it's suitable for home self-test and community hospital. [ABSTRACT FROM AUTHOR]

This study has investigated mechanical properties of perovskite-structured Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ (BSCF) oxygen transport membrane. The Young’s modulus and fracture toughness are determined by both macroscopic-scale and microscopic-scale methods. Both three-point and ring-on-ring bending tests as macroscopic-scale methods produce broadly similar results with a Young’s modulus, which is lower than that measured from micro-indentation method under a 10 N load. Young’s modulus and fracture toughness of BSCF show strongly dependent of the porosity. However, the fracture toughness of BSCF is independent of grain size. The fracture toughness determined by macroscopic-scale method is similar with that measured by microscopic-scale method. The crack shape of BSCF under a 10 N load is determined to be a median-radial mode. The intrinsic Young’s modulus and fracture toughness are determined to be 105.6 GPa and 1.49 MPa m 0.5 , respectively, according the Minimum Solid Area (MSA) model. Annealing decreases the fracture toughness of BSCF between RT and 800 °C. [ABSTRACT FROM AUTHOR]

Since the 2001 anthrax attacks, researchers have focused on the development of a bacterial spore biomarker detector with rapid response time and high sensitivity and selectivity. Hence, a ratiometric fluorescent nanosensor based on lanthanide-functionalized attapulgite (Atta) was designed and prepared using dye-doped Atta as an internal reference. Atta, which is famous because of Maya Blue, is a hydrated magnesium aluminum silicate present in nature, with pronounced adsorption and a large specific surface area rich in silicon hydroxyl. The adsorption of dye molecules benefits the formation of an internal reference with orange fluorescence. Meanwhile, silicon hydroxyl would be available for terbium (Tb 3+ ) complex grafting, which favors the sensitization of the bacterial spore biomarker. With increasing dipicolinic acid (DPA) concentrations, energy transfer from DPA to Tb 3+ gradually enhanced, thereby resulting in strong and predominant green fluorescence. The ratiometric fluorescence intensity is highly sensitive. It has a limit of detection of 9.8 nM, which is much lower than the infectious dosage of Bacillus anthracis spores (60 μM) for humans. The rapid response time (10s), high selectivity, and reliable and practical performances in actual applications make this ratiometric fluorescent nanosensor useful in the detection of biomarkers for various bacterial spores. Moreover, the reported construction of visual ratiometric detection system follows the sustainable development idea of ‘‘from nature, for nature, into the nature’’ and promotes the use of naturally renewable resources to produce promising and eco-friendly functional materials for various applications. [ABSTRACT FROM AUTHOR]

The effect of hydrogen on the tensile properties of AISI 304 K-TIG weld metal is investigated in this study. Fractographic analysis demonstrates a transition from quasi-cleavage/cleavage fracture to intergranular fracture in the brittle zone as the hydrogen-charging current density increases, which is attributed to the interplay of crystalline defect, hydrogen atoms, and α′ martensite transformation sites. It is believed that at low current density, α′ martensite nucleates and grows homogeneously in the interior of the grain. At high current density, the stress-induced α′ martensite forms preferentially at the grain boundary, which undergoes severe strain localisation and hydrogen atom segregation. [ABSTRACT FROM AUTHOR]

This paper herein studies subcritical crack growth ( SCG) behavior of a perovskite-structured Ba0.5Sr0.5Co0.8Fe0.2O3−δ ( BSCF) as an oxygen transport membrane material. The SCG behavior of BSCF is evaluated by a constant load method and constant stress rate method at room temperature ( RT) and 800°C in air, respectively. The low crack velocity measurements are carried out by ring-on-ring bending tests while the high crack velocity measurements by compact tension tests. The stress rates vary approximately from 0.1012 to 101.2 MPa/min. The fracture stress increases with increasing stress rate at 800°C. The SCG parameter, n, of BSCF is determined to be 24.32 and 13.83 at RT and 800°C in air, respectively. This indicates that BSCF is more susceptible to SCG at 800°C. The strength-probability-time ( SPT) diagram is constructed for design proposes. The stress for a lifetime of 40 years should not exceed 27.21 MPa at RT or 4.53 MPa at 800°C to assure a failure probability below 1%. [ABSTRACT FROM AUTHOR]

The present study evaluates the fracture strengths and the Weibull modulus of Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3−δ (BSCF) oxygen transport membranes by means of biaxial and uniaxial bending tests at both room temperature (RT) and 800 °C. The fracture strengths obtained from the biaxial bending tests are much lower than those obtained from the uniaxial bending tests while Weibull moduli (m) are similar. By utilising Weibull statistics the uniaxial strengths can be predicted from the biaxial values at both RT and 800 °C. Fracture surfaces at both RT and 800 °C show only a transgranular fracture mode. Failure origins are also determined by scanning electron microscope (SEM) based on the fractographic principles. Most defects determining the fracture strength of this particular material are found to be pores with a relatively large size. [ABSTRACT FROM AUTHOR]

Pyriproxyfen is an insect growth regulator that is widely used in public health and pest control in agriculture. Our previous studies have shown that trace amounts of pyriproxyfen in the environment can cause serious toxic effects in the non-target insect silkworm, including failing to pupate, metamorphose and spin cocoons. However, it is unknown why pyriproxyfen not only has no lethal effects on fifth instar larvae but also tend to increase their body weight. The midgut is the main digestive organs of the silkworm, our results showed that the residual of pyriproxyfen in the silkworm at 24 h after 1 × 10−4 mg/L pyriproxyfen treatment caused severe damage to the midgut microvilli, goblet cells, and nuclei of the silkworm, but body weight and digestibility of the larval were both increased. In addition, pyriproxyfen significantly (p < 0.05) increased the activities of digestive enzymes (α-amylase, trehalase, trypsin and lipase) in the midgut of silkworm. However, it caused down-regulation of ecdysone synthesis-related genes at the end of the fifth instar silkworm, decreased ecdysone titer, and prolonged larval instar. At the same time, pyriproxyfen also activated transcription of detoxification enzymes-related genes such as the cytochrome P450 enzyme genes Cyp9a22 and Cyp15C1 , the carboxylesterase genes CarE-8 and CarE-11 , and the glutathione S-transferase gene GSTo2. This study elucidated a novel toxicological effect of pyriproxyfen to insects, which not only expands the understanding of the effects of juvenile hormone pesticides on lepidopteran insects but also provides a reference for exploring the ecological security of non-target organisms. [Display omitted] • Elucidated a novel toxicological effect of pyriproxyfen to insects. • Trace pyriproxyfen had no lethal effects on fifth instar larvae of silkworm. • Trace pyriproxyfen caused severe damage to midgut cells of silkworm. • Trace pyriproxyfen increased the body weight and digestibility of silkworm larval. • Trace pyriproxyfen activated transcription of detoxification enzymes-related genes. [ABSTRACT FROM AUTHOR]

Comparative fatigue tests were conducted on as-welded, weld toe peened specimens before and after fatigue loading. Fracture surface, residual stress, microstructure and hardness were determined. The test results showed that as the pre-fatigue loading period extended, deeper cracks may have initiated and propagated and the fatigue life improvement decreased. The processes of ultrasonic peening on welded joints with existing cracks were modeled by finite element analysis. The numerical results indicated that the mechanism of UIT improving fatigue performance included two factors: compressive residual stress and the change of crack orientation. Both effects reduced as the crack became deeper. [ABSTRACT FROM AUTHOR]

Cumin and fennel are two types of food raw materials that have similar appearances but great differences in efficacy. Therefore, the efficient identification of these two types of food is very important to the related food processing industry and the development of food detection technology. In this study, a deep learning algorithm was designed to process Fourier NIR spectral data for the classification of cumin and fennel. The method was based on the difference in the signal intensity in NIR spectra between cumin and fennel, and the identification was performed by combining the improved multiscale fusion convolutional neural network (MCNN) and the bidirectional long-short-term memory network (BILSTM) based on NIR spectra. The classification accuracies of the MCNN and BILSTM models were 100% and 98.57%, respectively. The models have high sensitivity and fast analysis speed, which directly promote the development of real-time identification technology of cumin and fennel and verify the feasibility of deep learning algorithms in the field of food detection. [ABSTRACT FROM AUTHOR]