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Nanosprings demonstrate promising mechanical characteristics, positioning them as pivotal components in a diverse array of potential nanoengineering applications. To unlock the full potential of these nanosprings, ongoing research is concentrated on emulating springs at the nanoscale in terms of both morphology and function. This review underscores recent advancements in the field and provides a comprehensive overview of the diverse methods employed for nanospring preparation. Understanding the general mechanism behind nanospring formation lays the groundwork for the informed design of nanosprings. The synthesis section delineates four prominent methods employed for nanospring fabrication: vapor phase synthesis, templating methods, post-treatment techniques, and molecular engineering. Each method is critically analyzed, highlighting its strengths, limitations, and potential for scalability. Mechanical properties of nanosprings are explored in depth, discussing their response to external stimuli and their potential applications in various fields such as sensing, energy storage, and biomedical engineering. The interplay between nanospring morphology and mechanical behavior is elucidated, providing insights into the design principles for tailored functionality. Additionally, we anticipate that the evolution of state-of-the-art characterization tools, such as in situtransmission electron microscopy, 3D electron tomography, and machine learning, will significantly contribute to both the study of nanospring mechanisms and their applications.

Si-based rechargeable lithium-ion batteries (LIBs) have generated interest as silicon has remarkably high theoretical specific capacity. It is projected that LIBs will meet the increasing need for extensive energy storage systems, electric vehicles, and portable electronics with high energy densities. However, the Si-based LIB has a substantial problem due to the volume cycle variations brought on by Si, which result in severe capacity loss. Making Si-based anodes-enabled high-performance LIBs that are easy to utilize requires an understanding of the fading mechanism. Due to its distinct advantage in morphological changes from microscale to nanoscale, even approaching atomic resolution, electron microscopy is one of the most popular methods. Based on operandoelectron microscopy characterization, the general comprehension of the fading mechanism and the morphology evolution of Si-based LIBs are debated in this review. The current advancements in compositional and structural interpretation for Si-based LIBs using advanced electron microscopy characterization methods are outlined. The future development trends in pertinent silicon materials characterization methods are also highlighted, along with numerous potential research avenues for Si-based LIBs design and characterization.

Both factors, multilayer Feedforward Neural Networks (FFNs) and short-term synaptic plasticity (STP), are considered crucial in the transmission and processing of neural signals. In this study, a 10-layer FFN was constructed to study the impact of STP on neuronal activity propagation. Neurons within the same layer do not have direct connections; instead, neurons between adjacent layers are randomly connected with a specific probability. The findings indicate that synaptic plasticity can regulate the network's firing rate, synchronization, and output firing rate gain. Notably, short-term facilitation (STF) allows the network to exhibit high-pass filtering, while short-term depression (STD) achieves low-pass filtering. Combining STF and STD synapses in the FFN broadens the range of input firing rates effectively transmitted by the network. Increasing the proportion of STD-dominated synapses enhances the gain of low firing rate signals but reduces the gain of high firing rate signals. Adjusting the mix of synapses enables the network to implement bandpass filtering and control firing rate gain. These results underscore the effectiveness of modulating short-term synaptic plasticity in regulating neural activity propagation in FFNs. • A 10-layer FFN was constructed to investigate the effect of STP on spiking propagation. • Short-term facilitation makes the feedforward network high-pass filtering function. • Short-term depression makes the feedforward network low-pass filtering function. • A mix of STF and STD makes the FFN bandpass filtering function. • Adjusting the mixing proportion regulates the gain of firing rate in the network. [ABSTRACT FROM AUTHOR]

•Multi-tissue scRNA-seq analysis reveals 16 sub-clusters of immune cells in turbot.•Conserved B lymphocytes identities suggest its role in acute phase of infection.•Cytotoxicity- and regulatory-associated genes are identified in different T cells.

Trained immunity is classically characterized by long-term functional reprogramming of innate immune cells to combat infectious diseases. Infection-induced organ injury is a common clinical severity phenotype of sepsis. However, whether the induction of trained immunity plays a role in protecting septic organ injury remains largely unknown. Here, through establishing an in vivoβ-glucan training and lipopolysaccharide (LPS) challenge model in zebrafish larvae, we observe that induction of trained immunity could inhibit pyroptosis of hepatocytes to alleviate septic liver injury, with an elevated trimethyl-histone H3 lysine 4 (H3K4me3) modification that targets mitophagy-related genes. Moreover, we identify a C-type lectin domain receptor in zebrafish, named DrDectin-1, which is revealed as the orchestrator in gating H3K4me3 rewiring-mediated mitophagy activation and alleviating pyroptosis-engaged septic liver injury in vivo. Taken together, our results uncover tissue-resident trained immunity in maintaining liver homeostasis at the whole-animal level and offer an in vivomodel to efficiently integrate trained immunity for immunotherapies.

AbstractBased on the design and construction of the second Yangtze River bridge in Wuhu (hereinafter referred to as Wuhu Second Bridge), this article introduces the structural system of a full-floating cable-stayed bridge with four cable planes, a single-column tower and separated steel box girders. A series of innovative structural measures are taken to improve the safety and economy of the bridge, such as the looping stayed cable anchorage system, the diagonal damping constraint system, and the externally prestressed segmentally assembled box girders used in the approach bridge. In addition, finite element analysis software is used to study and analyse the mechanical characteristics of the bridge. Also, the reliability of the structural anchorage system and damping constraint system is verified. Finally, the construction technology adopted for Wuhu Second Bridge is briefly described.

The effective recycling of retired LiFePO4batteries serves dual purposes: addressing the resource supply-demand contradiction and mitigating environmental pollution. However, the existing recycling methods for waste LiFePO4batteries often entail high energy consumption, time consumption, complex procedures, or the use of substantial amounts of chemical raw materials, leading to increased recycling costs. Moreover, both methods generate toxic gases or discharge excessive pollutant-containing liquids during the recycling process, posing a risk of secondary pollution. Here, we introduce the application of ultrasound-assisted regeneration in waste LiFePO4cathode material directly. Ultrasound waves generate localized high temperature, high pressure, and intense shock wave jets to repair the lithium vacancy defects and anti-site defects in the waste LiFePO4. Based on the experimental findings, the regeneration of LiFePO4was achieved with impressive results. At an ultrasound power of 500 W and a duration of 50 min, the regenerated LiFePO4displayed a discharge specific capacity of 135.1 mAh∙g−1and an impressive capacity retention of 97 % after 100 cycles at a 1C (1C = 170 mA g−1) current density. This study presents a promising and environmentally friendly approach for recycling and regenerating retired LiFePO4batteries.

We proposed and experimentally demonstrated a novel method for generating a chiral beam with controllable intensity twist lobes and direction by using annular subzone (AS) vortex phase plates, which is composed of different ASs and different vortex phases. The phase distribution continuity between two adjacent ASs determines the intensity distribution of the light field. The rotated direction of the optical filed is determined by the topological charge sign. The number of intensity twist lobes is determined by the topological charge gradient between adjacent subzones. The experimental results show that this method is effective and practical, which offers broad potential applications in particle manipulation, chiral microstructure fabrication, and optical tweezers.

A high numerical aperture multifocal metalens was proposed based on well-designed Pancharatnam–Berry phase optical elements. Both circularly and linearly polarized incident lights could be tightly focused into diffraction-limited focal spots. Right and left circularly polarized focal spots could be realized simultaneously by illuminating a linearly polarized beam. The highest numerical aperture reached to 0.84 with full width at half-maximum of 263 nm. Moreover, we also presented a metalens whose optical elements are hybrid arranged and the metalens can realize spin-independent focusing with a numerical aperture of 0.8. The presented metalens has significant potential applications in particles manipulation and high-resolution imaging.

Aggregation-induced emission (AIE) imaging probes have recently received considerable attention because of their unique property of high performance in the aggregated state and their imaging capability. However, the tendency of AIE molecules to aggregate into micron long irregular shapes, which significantly limits their application in vivo, is becoming a serious issue that needs to be addressed. Here, we introduce a novel engineering strategy to tune the morphology and size of AIE nanoaggregates, based on flash nanoprecipitation (FNP). Quinolinemalononitrile (ED) is encapsulated inside properly selected amphiphilic block copolymers of varying concentration. This leads to a variety of ED particle morphologies with different sizes. The shape and size are found to have strong influences on tumor targeting both in vitro and in vivo. The current results therefore indicate that the FNP method together with optimal choice of an amphiphilic copolymer is a universal method to systematically control the aggregation state of AIE materials and hence tune the morphology and size of AIE nanoaggregates, which is potentially useful for precise imaging at specific tumor sites.

Traditional charge-conversion nanoparticles (NPs) need the breakage of acid-labile groups on the surface, which impedes the rapid response to the acidic microenvironment. Here, we developed novel rodlike charge-conversion NPs with amphiphilic dextran-b-poly(lactic-co-glycolic acid), poly(2-(dimethylamino) ethylmethylacrylate)-b-poly(ε-caprolactone), and an aggregation-induced emission-active probe through flash nanoprecipitation (FNP). These NPs exhibit reversible negative-to-positive charge transition at a slightly acidic pH relying on the rapid protonation/deprotonation of polymers. The size and the critical charge-conversion pH can be further tuned by varying the flow rate and polymer ratio. Consequently, the charge conversion endows NPs with resistance to protein adsorption at physiological pH and enhanced internalization to cancer cells under acidic conditions. Ex vivo imaging on harvest organs shows that charge-conversion NPs were predominantly distributed in tumors after intravenous administration to mice due to the robust response of NPs to the acidic microenvironment in tumor tissue, whereas control NPs or free probes were broadly accumulated in tumor, liver, kidney, and lung. These results suggest the great potential of the current FNP strategy in the facile and generic fabrication of charge-conversion NPs for tumor-targeting delivery of drugs or fluorescent probes.

Inflammasomes are intracellular protein complexes that drive the activation of inflammatory caspases. So far, four inflammasomes involving NLRP1, NLRP3, NLRC4 and AIM2 have been described that recruit the common adaptor protein ASC to activate caspase-1, leading to the secretion of mature IL-1β and IL-18 proteins. The NLRP3 inflammasome has been implicated in the pathogenesis of several acquired inflammatory diseases as well as cryopyrin-associated periodic fever syndromes (CAPS) caused by inherited NLRP3 mutations. Potassium efflux is a common step that is essential for NLRP3 inflammasome activation induced by many stimuli. Despite extensive investigation, the molecular mechanism leading to NLRP3 activation in response to potassium efflux remains unknown. Here we report the identification of NEK7, a member of the family of mammalian NIMA-related kinases (NEK proteins), as an NLRP3-binding protein that acts downstream of potassium efflux to regulate NLRP3 oligomerization and activation. In the absence of NEK7, caspase-1 activation and IL-1β release were abrogated in response to signals that activate NLRP3, but not NLRC4 or AIM2 inflammasomes. NLRP3-activating stimuli promoted the NLRP3–NEK7 interaction in a process that was dependent on potassium efflux. NLRP3 associated with the catalytic domain of NEK7, but the catalytic activity of NEK7 was shown to be dispensable for activation of the NLRP3 inflammasome. Activated macrophages formed a high-molecular-mass NLRP3–NEK7 complex, which, along with ASC oligomerization and ASC speck formation, was abrogated in the absence of NEK7. NEK7 was required for macrophages containing the CAPS-associated NLRP3(R258W) activating mutation to activate caspase-1. Mouse chimaeras reconstituted with wild-type, Nek7−/−or Nlrp3−/−haematopoietic cells showed that NEK7 was required for NLRP3 inflammasome activation in vivo. These studies demonstrate that NEK7 is an essential protein that acts downstream of potassium efflux to mediate NLRP3 inflammasome assembly and activation.

Poly(I:C) is a kind of chemosynthetic double-stranded RNA (dsRNA) analogue which could act as TLR3 agonist and induce IFN production. It is widely applied in anti-virus treatment and immunoregulation, as well as vaccine adjuvant in farmed animals. However, whether poly(I:C) could activate innate immune response to defense against bacterial infection remains unclear. In this study, we established a feeding trial model with different dose of poly(I:C) in turbot larvae, then challenged with Edwardsiella piscicidaafter 3–7 weeks resting period. The results show that feeding turbot with poly(I:C) exhibited a stronger inflammatory response and antioxidant stress ability, and significantly elevated the survival rate within the decreased bacterial loads. Importantly, the bacterial infection-induced white feces in hindgut of turbot were significantly alleviated after poly(I:C) feeding, and this administration induced protection could last for about 7 weeks. Taken together, these findings indicate that feeding turbot with poly(I:C) could enhance a long-term intestinal mucosal immunity in response to bacterial infection, suggesting that poly(I:C) might be a promising immunostimulant in aquaculture.

Hosts recognize cytosolic microbial infection via the nucleotide-binding domain-like receptor (NLR) protein family, triggering inflammasome complex assembly to provoke pyroptosis or cytokine-related caspase-1-dependent antimicrobial responses. Pathogens have evolved diverse strategies to antagonize inflammasome activation. Here, Edwardsiella piscicidagene-defined transposon library screening for lactate dehydrogenase (LDH) release in nlrc4−/−bone marrow-derived macrophages (BMDMs) demonstrates that genes clustered in the bacterial arginine metabolism pathway participate in NLRP3 inflammasome inhibition. Blocking arginine uptake or putrescine export significantly relieves NLRP3 inflammasome inhibition, indicating that this bacterium rewires its arginine metabolism network during infection. Moreover, intracellular E. piscicidarecruits the host arginine importer (mCAT-1) and putrescine exporter (Oct-2) to bacterium-containing vacuoles, accompanied by reduced arginine and accumulated cytosolic spermine. Neutralizing E. piscicida-induced cytosolic spermine enhancement by spermine synthetase or extracellular spermine significantly alters NLRP3 inflammasome activation. Importantly, accumulated cytosolic spermine inhibits K+efflux-dependent NLRP3 inflammasome activation. These data highlight the mechanism of bacterial gene-mediated arginine metabolism control for NLRP3 inflammasome evasion.

Uncoated weathering steel can significantly reduce the life cycle cost of bridges and the difficulty of maintenance during operation. However, weathering steel is not a maintenance-free material. Design and construction errors, topography, de-icing salt and other factors are likely to cause severe corrosion of weathering steel. Therefore, effective inspection and maintenance planning is essential to ensure that weathering steel bridges can reach expected service life. Weathering steel bridges must be regularly inspected to check the corrosion of weathering steel in important parts, and evaluations shall be made to develop maintenance plans. Previous investigations show that the appearance of weathering steel's rust layer can effectively judge its stability. Therefore, the corrosion condition of weathering steel can be judged by different rating of the appearance of the rust layer. Meanwhile, corresponding maintenance measures will be formulated.

Bacterial phosphothreonine lyases have been identified to be type III secretion system (T3SS) effectors that irreversibly dephosphorylate host mitogen-activated protein kinase (MAPK) signaling to promote infection. However, the effects of phosphothreonine lyase on nuclear factor κB (NF-κB) signaling remain largely unknown.

Bacteria utilize type III secretion systems (T3SS) to deliver effectors directly into host cells. Hence, it is very important to identify the functions of bacterial (T3SS) effectors to understand host-pathogen interactions.