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To facilitate the practical deployment and engineering implementation of multi-robot coordination for biomimetic underwater spherical robots (BUSRs), it is imperative to develop a formation tracking control method with a simple structure, a small number of tunable parameters, convenient parameter tuning and strong anti-disturbance capability. This study proposes a formation controller integrating virtual structure (VS), consensus protocol, and parallel output-velocity-type active disturbance rejection control (POV-ADRC), denoted as VS-C-POV-ADRC. A rotating global (RG) coordinate system is established to decouple robot positions from heading angles, which makes the parameter tuning more convenient. A double-loop control architecture is constructed, where the outer consensus control loop generates the desired velocity for each robot based on virtual-structure reference positions, and the inner POV-ADRC loop achieves high-precision velocity tracking. The proposed controller features a compact structure with only five adjustable parameters per motion direction, realizing easy engineering implementation and adaptation to the limited computing capacity of BUSRs. The simulation and experiment results demonstrate that the proposed algorithm enables robots to maintain a stable formation and achieve trajectory tracking accuracy within one body length, while exhibiting superior disturbance rejection. The proposed method provides a feasible and practical solution for BUSR formation control.

Hastelloy C276 is extensively used in aerospace, chemical, and high-temperature engineering systems, yet its poor machinability leads to rapid tool degradation and reduced productivity. This study develops a comprehensive machine-learning (ML) framework to model and predict flank-wear progression during the turning of Hastelloy C276 under Dry, Minimum Quantity Lubrication (MQL), and nanoparticle-assisted MQL environments. A series of controlled machining experiments were performed by varying cutting speed, feed, depth of cut, and machining length, generating more than 700 labeled wear samples measured using optical microscopy. Four ML models-Ridge Regression, Decision Tree, Random Forest, and Support Vector Regression- were trained using five-fold cross-validation for hyperparameter optimization, and their final performance was evaluated on an independent test dataset. Among them, Random Forest exhibited the highest predictive accuracy (R2 = 0.982, MAE = 0.004 mm, RMSE = 0.006 mm), effectively capturing nonlinear wear behavior associated with thermal-mechanical interactions. Experimental results confirmed the strong influence of lubrication environment on tool life, with nano-MQL reducing average flank wear by 28-35% compared to Dry machining due to enhanced cooling and tribo-film formation by hBN nanoparticles. Feature-importance analysis further identified lubrication condition, machining length, and feed rate as the dominant predictors governing wear evolution. The study demonstrates that reliable tool-wear prediction can be achieved using machining parameters alone-without additional sensors-highlighting the potential of ML-driven frameworks for future intelligent tool-condition monitoring and sustainable machining of difficult-to-cut superalloys.

Planar honeycomb structures, especially biomimetic hexagonal honeycombs, are widely used in energy-absorbing equipment because of their excellent out-of-plane deformation resistance. However, their significant mechanical anisotropy, manifested by the large discrepancy between out-of-plane and in-plane responses, greatly restricts their broader applications. Inspired by spiral-reinforced thin-walled biological tubular systems, such as animal tracheae and plant vessels, this study proposes a biomimetic reinforcement strategy by embedding spiral structures along the thin walls of planar honeycombs. To validate the feasibility of the proposed design, biomimetic honeycomb specimens were fabricated using 3D-printing technology and tested under compression along different loading directions. Furthermore, a numerical model validated against the experiments was developed to reveal the underlying enhancement mechanism. The results demonstrate that the proposed biomimetic honeycomb preserves the favorable out-of-plane performance of the conventional hexagonal honeycomb, while improving the in-plane energy absorption capacity by up to 70%. The biomimetic spiral reinforcements enable more effective load transfer under multidirectional loading, resulting in a more uniform plastic stress distribution over the entire structure and activating a larger deformation region for energy dissipation. The present work provides a bioinspired strategy for developing lightweight energy-absorbing structures for potential applications in aerospace, rail vehicles, marine engineering, and civil structures.

Double-panel structures (DPSs) have wide applications in noise control engineering, but their sound insulation (SI) performances deteriorate rapidly in the low-frequency range. To make up for this deficiency, an active control strategy through controlling the boundary conditions of the sound field is presented to improve the SI performance of DPSs. A controllable plate as a controllable boundary condition is incorporated into the boundaries of the interlayer sound field (ISF), and it can be actively controlled by applying control forces. The control forces are optimized by three control objectives, i.e., minimization of kinetic energy of the radiation panel, minimization of acoustical potential energy of the ISF, and minimization of radiation sound power of the low-order acoustic radiation modes. The control effects, control mechanism, and the influences of the geometrical parameters, number of controllable plates, and location of control force on the SI performance are investigated. The results indicate that in the low-frequency range, all three active control strategies can enhance the SI performance of a DPS. And the modal response calculations indicate that the control mechanism belongs to the acoustical and structural modal suppression and rearrangement. This research provides a solution for improving the low-frequency SI performance of engineering structures.

Fused filament fabrication (FFF) three-dimensional (3D) printing technologies offer new opportunities for fabricating customizable, low-cost platforms for tissue engineering applications. Here, we developed and characterized 3D-printed scaffolds using conductive thermoplastic polyurethane (cTPU) filaments and evaluated their mechanical, electrical, and biological performance in vitro. Dynamic mechanical analysis (DMA) across a range of temperatures and frequencies revealed that both TPU and cTPU exhibit temperature- and rate-dependent elastic moduli, with cTPU showing enhanced mechanical stiffness due to the incorporation of conductive fillers. Electrical testing confirmed that cTPU exhibited a stable conductivity (∼1-2 mS/cm) resembling physiological conditions. Surface characterization showed that cTPU was significantly more hydrophilic and exhibited higher nanoscale roughness, both of which are favorable for cell-material interactions. Mouse embryonic fibroblasts (MEFs) cultured on both scaffolds showed high viability (>85%) and significant proliferation. Notably, immunofluorescence analysis of cultured hippocampal neurons revealed significantly higher density of neuronal networks represented by higher microtubule-associated protein 2 (MAP-2)-positive cell density, greater MAP-2 area coverage, larger average MAP-2 cell area, and enhanced postsynaptic density protein 95 (PSD-95) expression on cTPU scaffolds. Together, these results demonstrate that FFF 3D-printed cTPU platforms can support long-term neuronal growth and synaptic maturation, offering promising applications in neural tissue modeling and bioelectronic interfaces. Practical Application: Characterizing soft viscoelastic materials whose properties strongly depend on temperature and strain rate is challenging and typically requires extensive testing across multiple conditions. Using a single-specimen Dynamic Mechanical Analysis-based mechanical testing method and a viscoelastic-elastic transformation that converts frequency-domain viscoelastic measurements into elastic constants over a broad range of test conditions, validated by tensile tests, we efficiently generated reliable modulus data across a range of conditions, enhancing testing throughput without sacrificing accuracy. As a case study, we demonstrate the successful fabrication and comprehensive characterization of FDM 3D-printed conductive TPU (cTPU) scaffolds for potential applications in neural tissue modeling and bioelectronic interfaces, with the results positioning cTPU composites as cost-effective, tunable, cytocompatible, and electrically active platforms capable of supporting neuronal growth and function.

The fast-evolving IT sector necessitates intelligent electromagnetic interference (EMI) shielding materials capable of real-time, environment-responsive. While current approaches based on reconstructing conductive networks through mechanical strain enable dynamically responsive shielding, but face a narrow tuning range, inadequate stability, and practical limitations. To address this, we propose an electric/magnetic field synergistic regulation strategy. This approach enables precise control over the alignment angle between reduced graphene oxide (rGO) and nickel nanowires (NiNWs) by manipulating the external field direction, producing rGO@NiNWs/polyimide aerogels with 3D ordered networks. Leveraging this design, the aerogels achieve reversible, wide-range tuning of EMI shielding performance through simple physical rotation, enabling reliable "on/off" switching capability. The oriented structure also optimizes both filler interconnection efficiency and interfacial polarization. With an rGO@NiNWs content of 80 wt.% and an inter-phase angle of 90°, the aerogels demonstrate excellent ultra-wideband EMI shielding performance across gigahertz and terahertz bands, with an average shielding effectiveness of 85 dB in the terahertz band, alongside good stability in extreme environments. Finite element simulations further reveal how the spatial configuration of rGO@NiNWs governs the shielding behavior and intelligent response mechanism. This study paves the way for next-generation intelligent electromagnetic protection materials, with promising potential for aerospace and wearable applications.

This paper proposes an ultrasonic motor capable of achieving both single-mode and multi-mode coupled operation. The stator structure is simple and fully symmetrical, consisting of two parallel sandwich-type vibrators. The motor achieves flexible switching between single-mode and multi-mode coupled operation by selectively exciting the longitudinal vibration modes of the left and right vibrators. Due to the symmetry of the dual-vibrator stator structure, the frequencies of the two coupled modes are naturally close, and improving motor design efficiency. Moreover, this dual-vibrator structure enables the motor to maintain consistent bidirectional output characteristics even when operating in single-mode configuration. Since piezoelectric ceramics operate in the d33 mode with high electromechanical coupling capability, the sandwich structure effectively enhances the output performance of the motor. This thesis first details structure and operating principles of the motor. Subsequently, finite element analysis software is employed to conduct modal analysis, frequency and transient analysis of the stator, validating its feasibility. Finally, a prototype is fabricated and tested on an experimental platform to evaluate its output performance. In single-mode operation, the prototype achieves a maximum speed of 434 mm/s, a maximum load of 0.8 kg, and a maximum efficiency of 5.03 %. In multi-mode coupled drive mode, it achieves a maximum speed of 612 mm/s, a maximum load of 1 kg, and a maximum efficiency of 3.69 %. The motor also achieves a resolution as high as 8.1 nm. The motor features a compact structure and simple drive mechanism, enabling seamless switching between two operating modes. It exhibits relatively favorable output characteristics, making it suitable for various precision drive applications such as optical instruments, medical equipment, and aerospace systems.

In the present investigation, friction stir processing (FSP) is implemented to develop the tungsten carbide (WC) nanoparticle-reinforced aluminum alloy Al6061-T6. The tensile properties of the Al6061-T6/WC surface nanocomposite were evaluated in relation to the volume fraction of WC nanoparticles, the number of passes, rotation speed, and traverse speed. The experiments were designed using the Box-Behnken Design (BBD) of response surface methodology (RSM). For identifying the significant variables and interaction implications, analysis of variance (ANOVA) was performed. The models generated demonstrate that rotating speed is the most significant variable and transverse speed is of little importance. Heat input to FSP increases as traverse speed decreases and tool rotational speed increases. Increasing the number of FSP passes effectively broke the coarse and dendritic clusters, refined the matrix grains, and dynamic recrystallization (DRX) resulting in equiaxed grains that, through restricted dislocation activity, exhibit tensile behavior. Furthermore, the extreme plastic deformation and heat production during FSP results in the breakage of WC particles and coarse particles, the removal of porous holes, and DRX of an ultrafine grain-sized structure. The optimized surface nanocomposite with the highest tensile strength (315 MPa), yield strength (221 MPa), and elongation (9.7%) was achieved at volume fraction 2%, number of passes 5, rotation speed 1000 rpm, and traverse speed 30 mm/min. The surface composite that developed has been identified as an appropriate material for the automotive, aerospace, marine, defense, and transportation sectors, among others, that require lightweight and improved surface qualities.

The trade-off between safety and energy content has long been a central challenge in the design of energetic materials. Here we propose a TATB-inspired design strategy for high-energy, insensitive explosives: secure intrinsic safety at the electronic and molecular scales, and achieve synergistic optimization of safety and detonation performance at the crystal scale by enforcing planar packing motifs. Using fused five- and six-membered nitrogen-containing aromatic rings as the scaffold, and combining nitro, amino, and N-coordinated oxygen substituents, we constructed an initial molecular library of 1 00 413 compounds and applied five rounds of high-throughput virtual screening (oxygen balance, substituent counts, synthetic feasibility, planarity, predicted detonation velocity) to progressively down-select targets. Crystal structure prediction was then performed for 100 candidate molecules using USPEX coupled with GFN1-xTB, yielding ten compounds with planar, layered packing motifs. Theoretical evaluation indicates that mol-392 attains a calculated detonation velocity of 8541 m s-1 and a predicted sensitivity at least comparable to TNT, demonstrating excellent overall performance. Furthermore, energy decomposition and correlation analyses identify van der Waals (dispersion) interactions as the dominant determinant of crystal density in these systems. This study validates the practicality of the TATB-like design strategy, provides a route for the rational discovery of insensitive high explosives, elucidates mechanisms governing crystal density in planar layered packings, and highlights the value of combining high-throughput virtual screening with crystal engineering in energetic-materials development.

Titanium dioxide (TiO2)-based conductive coatings are promising for aerospace, marine, and energy applications because of their environmental friendliness and low cost. However, yet their practical use is hindered by high photogenerated charge recombination and poor visible-light response. Although constructing triphasic heterostructures can enhance performance, their high-temperature instability remains a critical barrier. Herein, a synergistic strategy combining Co/Ni co-doping and graphene compositing is used: lattice stress caused by ionic radius differences generates a pinning effect that stabilize the anatase/brookite/rutile triphasic heterostructure, while chemical bonding with graphene constructs multilevel conductive pathways (Ti-O-C, Co-O-C, Ni-O-C). The built-in electric field at the triphasic heterointerfaces drives directional charge separation, and the highly conductive graphene network enables efficient carrier migration from the lattice to the interface, synergistically enhancing conductivity and establishing a dual charge transport mechanism. Structural characterization and theoretical calculations confirm that this strategy effectively stabilizes the multiphase structure and constructs multilevel conductive pathways. The resulting CN-T/G coating exhibits a low resistivity of 0.23 Ω · cm (a 79.6% reduction), a protection efficiency of 91.25%, super-hydrophobicity (water contact angle of 159.25°), and photocatalytic self-cleaning ability. This work provides a feasible design strategy for creating efficient, stable, and multifunctional TiO2-based conductive materials.

Biological systems regulate motion and suppress unwanted vibrations through learning, adaptation, and predictive control under uncertainty. Inspired by these principles, Bayesian system identification has emerged as a powerful framework for modeling and estimation, particularly in the presence of uncertainty in structural systems. Flexible structures in aerospace and robotics require advanced control to mitigate vibrations under model uncertainty. This paper proposes a data-driven strategy leveraging a Gaussian Process (GP) integrated within a Nonlinear Model Predictive Control (NMPC) framework. The core innovation lies in using a Gaussian Process Nonlinear AutoRegressive model with eXogenous input (GP-NARX) as a probabilistic predictor to capture structural dynamics while quantifying uncertainty. The operational mechanism involves a tight coupling where the GP provides multi-step-ahead forecasts that the NMPC optimizer uses to minimize a cost function subject to constraints. Validated through simulations on Duffing oscillators, linear oscillators, and cantilever beams, the GP-NMPC achieved an 88.2% reduction in displacement amplitude compared to uncontrolled systems. Quantitative analysis shows high predictive accuracy, with a Root Mean Square Error (RMSE) of 0.0031 and a Standardized Mean-Squared Error (SMSE) below 0.05. Furthermore, Mean Standardized Log Loss (MSLL) evaluations confirm the reliability of the predictive uncertainty within the control loop. These results demonstrate strong performance in both regulation and tracking tasks, justifying this Bayesian-predictive coupling as a powerful approach for high-performance structural vibration control and a potential foundation for bio-inspired mechanical design.

Alveolar epithelial cell type 1 (AT1) and type 2 (AT2) cells make up the saccular gas exchange units of the lung, called alveoli. Formation of alveoli during lung development accounts for the expansive surface area of the lung, allowing for proper respiration and delivery of oxygen to the body. Due to their delicate structure, alveoli are susceptible to injury caused by environmental exposures, such as inhaled cigarette smoke and heavy metals. Chronic exposure to these toxicants can exacerbate preexisting conditions such as asthma or contribute to the progression of lung diseases, such as chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), and cancer. AT2 cells play a key role in injury repair and regeneration of the distal lung and there is widespread interest in their use as cellular models for lung disease in vitro. However, while immortalized cell lines derived from airway epithelial cells were successfully generated decades ago, human adult alveolar epithelial cell lines have proven to be more difficult to establish due to their limited proliferative capacity. Here we describe an extensive end-to-end method for deriving immortalized alveolar epithelial cells (AECs), termed "AEC-tLgT cells," from normal human lung tissue. We first outline a detailed procedure to isolate AT2 cells. We then outline our optimized method for immortalizing AT2 cells to generate polyclonal cell lines. We next describe a three-dimensional co-culture system to induce lung organoid formation from immortalized AT2 cell lines. Finally, we describe a procedure for studying cigarette smoke and nickel exposure using immortalized AT2 cell lines to investigate environmental toxicity. These protocols will enable users to generate AEC models from donors with defined genetic, demographic, and clinical backgrounds, facilitating the study of differential susceptibility to environmental exposures and risk for distal lung diseases. © 2026 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Isolation and purification of human AT2 cells Basic Protocol 2: Immortalization of AT2 cells and maintenance of resulting AEC lines Basic Protocol 3: Determination of organoid formation ability Basic Protocol 4: Treatment of immortalized AEC lines to study environmental exposures.

Omnidirectional locomotion offers superior adaptability and maneuverability over uni-/bidirectional movement, with spherical structures being ideal due to their zero turning radius and geometric stability on complex terrains. However, existing spherical robots rely on embedded control components and onboard power sources, inevitably increasing design complexity, weight, and cost. Herein, we developed a tumbleweed-inspired rolling robot (Twirlbot) to achieve the hollow spherical architecture by weaving photoactive/passive bilayer strips. The Twirlbot demonstrated autonomous rolling under constant light, enabling multiple functionalities, including omnidirectional locomotion, slope climbing, trampling resistance, cargo transport, self-correction, wind resistance, and adaptation to diverse terrains and environments. These features endowed the Twirlbot with great potential for real-world applications, such as self-sustained seed-sowing, daylight-driven commuting, and autonomous underwater wiring. Notably, the structural design was generalizable to other systems, including commercial materials, enabling substantial cost reduction (less than one-tenth that of existing autonomous untethered robots) and thereby presenting a promising route toward next-generation untethered, self-sustained robotic systems.

Norepinephrine (NE) in the peripheral nervous system plays crucial roles in regulating peripheral organs in health and disease. However, the spatiotemporal dynamics of sympathetic NE release and its underlying mechanisms remain poorly characterized due to technical challenges. Here, we developed and validated a Slice ElectroChemistry (SEC) method to record sympathetic NE release in heart slices with combined super-resolution and high sensitivity at 1 μm × 1 ms × 1 nM as in patch-clamp recordings. By using the SEC method, we revealed the increased NE release, impaired NE reuptake, increased releasable NE-vesicle pool, and impaired vesicle recycling of sympathetic nerves in the heart of transverse aortic constriction-induced heart failure (HF) mouse model, and defined the increased expression of Cav2.2 calcium channel as a central mechanism mediating the facilitation of NE release and thus the pathogenesis of HF, clarifying a longstanding puzzle about the kinetic changes of cardiac sympathetic NE release in HF. Beyond the heart, SEC enables NE release recording in other peripheral organs and human tissues, providing a robust toolset to investigate sympathetic NE dynamics across diverse pathophysiological conditions.

The demand for high-energy-density and fast-charging solid-state lithium metal batteries (SSLMBs) often subjects practical devices to internal thermal loads, making high-temperature operation a common operational condition rather than an isolated scenario. To address the interfacial degradation and dendrite growth accelerated by such thermomechanical stresses, we developed a composite gel electrolyte (CGE) by incorporating an optimal concentration of active Li6.4La3Zr1.4Ta0.6O12 (LLZTO) into a fluoropolymer network. The abundant Lewis acidic sites on the LLZTO surfaces promote competitive solvation decoupling by interacting with anions, thereby modulating the primary solvation sheath of Li+. This localized modulation lowers the lithium-ion migration activation energy to 0.248 eV and facilitates a dual-interfacial passivation mechanism. Specifically, a rigid, inorganic-rich solid electrolyte interphase (SEI) forms to suppress morphological instability at the lithium anode, while an organic-dominated cathode electrolyte interphase (CEI) enhances the oxidative stability up to 4.3 V. As a result, symmetric cells demonstrate stable electrodeposition for over 450 h at 80 °C and 0.5 mA cm-2. Furthermore, NCM811/Li full cells utilizing this CGEs exhibit significantly improved thermal resilience and cycling stability.

Dissimilar welding of titanium alloys to stainless steels offers the potential to combine lightweight, corrosion-resistant titanium with the toughness and cost-effectiveness of steel, yet the formation of brittle Ti-Fe intermetallic compounds (IMCs) at the interface has long prevented its reliable applications. This study examines the role of tantalum interlayer thickness in controlling intermetallic phases evolution and enhancing the mechanical response in pulsed gas tungsten arc welded (P-GTAW) Ti-6Al-4V/SS304 joints. Composite interlayer consisting of Tantalum (Ta) foils of 0.1, 0.3, and 0.5 mm thickness combined with Cu filler was introduced at the interface, and the resulting welds were evaluated through ultimate tensile strength (UTS), microhardness, and detailed microstructural characterization using scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) and X-ray diffraction (XRD) supported by fractography analysis. The results demonstrate that increasing interlayer thickness progressively suppressed the formation of Ti-Fe IMCs, refined the fusion zone grain structure, and promoted the development of Cu and Ta based phases. The joints with thickest Ta foil (0.5 mm) depicted high maximum strength (297 MPa), improving by 75% compared to the thinnest interlayer and microhardness profiles becoming smoother across the fusion boundary. These findings confirm that interlayering is an effective method to mitigate brittle phase formation in dissimilar Ti-SS welds. The improvements demonstrated underscore tantalum's potential for aerospace and structural applications are required, where both high strength and reliability are required.

Artificial biomolecular condensates have emerged as powerful tools for controlling cellular behaviour. Here we introduce a method to build artificial condensates within living mammalian cells by designing modular RNA motifs composed of a single short RNA strand. These condensates emerge spontaneously, creating RNA-rich compartments that remain separated from their surrounding environment. The RNA sequences include stem-loop domains that fold as the RNA is transcribed, and then condense in the nucleus and cytoplasm through loop-loop interactions. These sequences can be optimized and diversified, enabling the generation of distinct, non-mixing condensate populations and the programmable control of their subcellular localization. The RNA motifs can also be modified to recruit small molecules, proteins and RNA molecules in a sequence-specific manner to the RNA-rich phase. By introducing RNA linkers, we can build condensates with multiple subcompartments, whose organization can be controlled by tuning the linker stoichiometry. These artificial condensates provide a versatile platform for studying and manipulating molecular functions inside living cells.

Children and youth with physical disabilities face significant psychosocial challenges compared to their able-bodied peers. Medical specialty camps provide space where children can enjoy a typical camp experience alongside peers with similar conditions, offering programming and support tailored toward various levels of ability. This paper aimed to assess the impact of such camps on the psychosocial well-being of children with physical disabilities. A literature search performed in PubMed and Science Direct uncovered n = 33 research articles meeting the inclusion criteria. The existing literature consists of a mixture of qualitative and quantitative studies, collectively suggesting that medical specialty camps can lead to measurable improvements in children's quality of life, self-esteem, and self-perception, while also fostering positive social connections, enjoyment, belonging, and empowerment. However, questions remain about the long-term benefits of these camps, with extinguishing effects potentially being offset by follow-up programming. The absence of control data limits the strength of the conclusions that can be drawn. This review builds on the body of literature suggesting that medical specialty camps offer positive improvements to the lives of children and youth with illnesses and disabilities. Also, it suggests key components of effective research in this field, as well as avenues for future study.

Human induced pluripotent stem cell-derived cardiomyocytes are valuable for studying cell-cell communication and synchronization, but remain immature and often lack robust electrical and mechanical coupling. To address this, we investigated gap junction-mediated communication and developed plasma membrane vesicles enriched in functional connexin hemichannels, termed Connectosomes, to enhance intercellular coupling. Connectosomes display properly oriented connexins and enrich the Cx43 expression at cell-cell borders between cardiomyocytes. Through mathematical modeling and experimental validation, we demonstrate that Connectosome incorporation reinforces endogenous gap junctions, promotes synchronous calcium transients, and improves spatial coordination of beating across networks. Mechanistic studies using engineered cell lines with tagged connexin-43 confirm that channel orientation and functionality are critical, supporting a model in which Connectosomes contribute to gap junction coupling. These results show that Connectosomes can synchronize the beating of immature cardiomyocytes by boosting electrochemical communication, laying the groundwork for future therapeutic advances.