Search Results (1,420)

In vitro neurovascular unit (NVU) models are essential for reproducing blood–brain barrier (BBB) transport and neurovascular cell interactions. However, the literature remains fragmented: biomaterial chemistry, fabrication parameters and organ-on-a-chip architecture are commonly evaluated in isolation, while inconsistent reporting of matrix properties, processing history, cell source, flow and barrier readouts prevents head-to-head comparison and the extraction of transferable design rules. To address this gap, this review integrates biomaterials, manufacturing technologies and organ-on-a-chip engineering within a unified material–process–structure–function framework. We translate endothelial junctions, basement-membrane components and perivascular cells into experimentally actionable material requirements; compare natural, synthetic, semisynthetic and decellularized extracellular-matrix hydrogels; and examine crosslinking, peptide functionalization, stimuli responsiveness, composite-network formation and preparation methods. Findings from Transwell, microfluidic, tubular, self-assembled and 3D-bioprinted BBB systems are used to relate matrix stiffness, degradability, ligand density, permeability, device-body material and fabrication route to barrier maturation, analytical access and reproducibility. By defining matched controls and minimum reporting requirements for chemistry, mechanics, transport and processing, this review provides a practical basis for next-generation BBB models that can improve permeability and efficacy screening in drug discovery, reproduce disease- and patient-specific barrier dysfunction, and support individualized response testing with iPSC- or patient-derived cells. Full article

The rapid transition toward electrified mobility and climate neutrality has prioritized the structural and environmental optimization of battery electric vehicle (BEV) subsystems. While vehicle lightweighting enhances operational efficiency, the production phase of structural enclosures and battery cells frequently introduces severe environmental and economic impacts and supply chain vulnerabilities. This study presents a comprehensive cradle-to-gate environmental life cycle assessment (LCA), life cycle costing (LCC), and semi-quantitative social assessment of alternative battery housing materials and battery cell architectures. To achieve a functionally accurate comparison, alternative materials, including a novel recyclable thermoplastic acrylic sheet molding compound (SMC), commercial thermoset SMCs, aluminum (AlMg₃), and stainless steel, are evaluated using an analytical stiffness- and strength-equivalent methodology across three real-world geometric demonstrators. Simultaneously, lithium iron phosphate (LFP) liquid electrolyte prismatic cells and solid-state polymer pouch cells are assessed. Material-level results indicate that, while aluminum minimizes the structural mass, primary aluminum manufacturing exhibits the highest global warming potential and processing costs. Conversely, Polytec SMC and Elium SMC achieve the lowest environmental impacts alongside competitive total production costs. At the cell level, prismatic LFP architectures display superior environmental performance compared to solid-state pouch cells, which suffer from energy-intensive processing and lower volumetric capacity normalization. Demonstrator-level aggregation reveals that the electrochemical cells heavily dominate the environmental and economic footprint of the complete assembly, with the housing accounting for less than 5% of the total global warming potential (GWP) and 1% of the total costs. The social assessment reveals moderate and comparable performance across all systems, with slight advantages for thermoplastic composite-based configurations in terms of circularity potential and innovation perception. Overall, the study highlights the critical importance of the cell architecture and manufacturing processes in determining battery system sustainability, while demonstrating the relevance of lightweight composite housings in reducing the structural mass with a minimal environmental penalty. Full article

A polyurea-coated carbon fiber reinforced plastic (CFRP) laminated structure is designed to enhance the impact resistance of lithium-ion batteries against ground impact. This paper presents a numerical simulation to investigate the influence of a polyurea-coated CFRP battery pack bottom plate on mitigating battery damage under ground impact conditions. A novel three-dimensional finite element model of the polyurea-coated CFRP laminate, incorporating a hyper-viscoelastic material model for the polyurea coating and an orthotropic model for the CFRP, is established to analyze the impact response and damage behavior of the laminate. The simulated impact peak force, energy absorption, and maximum crack length of the polyurea-coated CFRP laminate are all within 5% of the experimental results. Based on this validated three-dimensional model, a new battery pack simulation model is developed. The battery module model innovatively adopts a hybrid approach that combines homogenized battery module models and detailed battery module models, enabling accurate simulation of localized cell damage and failure during collisions while significantly improving computational efficiency. The punching process after perforation of the polyurea-coated CFRP laminate, the subsequent crack propagation of the plate, and the local deformation modes of individual cells are clearly predicted by the global model. Battery shortening is recorded as an important indicator of internal short circuits and potential thermal runaway. A parametric study is carried out, and several underlying rules are revealed: the front coating method leads to a greater reduction in battery damage, and the stiffness–toughness interplay between the polyurea coating and the carbon fiber composite is identified as a critical factor governing battery damage. This study provides important insights for the design of protective structures for battery packs against ground impact. Full article

The performance of a Proton Exchange Membrane Fuel Cell (PEMFC) stack is largely determined during assembly, where component materials, sealant selection, and clamping force jointly influence both sealing effectiveness and interfacial losses. These factors interact through coupled mechanical, thermal, and electrical phenomena. Although detailed multiphysics models can accurately capture these effects, their high computational cost limits their application in parametric analyses and optimisation studies. The Equivalent Stiffness Model (ESM) provides an efficient alternative, representing each stack component as a simplified stiffness formulation. Starting from an earlier ESM that reproduces the nonlinear compression of the Membrane Electrode Assembly (MEA) and sealants, this work adds the calculation of the electrical contact resistance at the Gas Diffusion Layer (GDL)–Bipolar Plate (BPP) interface and the resulting GDL porosity. Given the large number of input parameters, a Design of Experiments (DoE) approach systematically explores a wide range of stack configurations and operating conditions. The analysis shows that GDL type, sealant properties, and clamping force are the main drivers of assembly-related performance, whereas BPP material and thermo-hygrometric conditions become more influential during operation. These results provide quantitative guidance on which design and operating choices most strongly affect stack behaviour and under which conditions. Full article

Porous Ti-6Al-4V lattice implants combine high specific strength, osseointegrative porosity, and compatibility with additive manufacturing, but conventional stiffness tuning through porosity, pore size, or unit-cell topology compromises biological pore requirements. This study presents a computational design framework in which structural kurtosis, the normalized interlayer offset between neighboring layers of a periodic cubic lattice, regulates elastic response at fixed global porosity. Closed-form expressions for the effective modulus are derived from first principles: the aligned configuration from the axial load-bearing area fraction, and the interlayer-shifted configuration from Euler–Bernoulli beam theory for guided-end connecting members. The derivations reproduce the Gibson–Ashby exponents n = 1 and n = 2, replacing the previously asserted power law, and a calibrated one-parameter interpolation bridges intermediate offsets. At 65% porosity, the effective modulus falls from 16.5 GPa in the aligned lattice to 2.64 GPa in the shifted lattice. A local-yield analysis based on peak bending curvature gives recoverable elastic strains of 1.37% at 89% porosity and 0.68% at 65%; the compliance-based values of 20.5% and 5.12% are kinematic upper bounds that neglect plastic hinging. A prefactor-free benchmark shows that obtaining the same 6.25-fold reduction by increased porosity alone would require 85.9–94.4% porosity and 0.17–0.28 mm struts, outside the osseointegration window and the resolution of selective laser melting. A GAN-CAD-FEA workflow reproduced the analytical moduli to within 7% across six design cases. All results are analytical and numerical; no specimens were fabricated or tested, and experimental validation remains required. Full article

The flexural behaviour of body-centred cubic (BCC) lattice beams fabricated by stereolithography remains supported by limited experimental evidence, and available homogenized beam models are rarely confronted with data in the combined regime of high relative density, non-slender struts, and low span-to-depth ratios. This work presents an experimental campaign on polymeric BCC lattice beams with three unit-cell edge lengths ($L=3$, 4, and 5 mm) and a constant strut-to-cell ratio $R/L=1/6$, yielding a relative density ${\rho }^{*}\approx 0.423$. Specimens were tested under uniaxial compression and three-point bending for nine combinations of geometry. The experimental data are compared with three analytical frameworks: a classical Euler–Bernoulli homogenized beam model and a BCC-specific shear-corrected formulation at the structural level, both evaluated without calibration to the bending tests, together with a strain-gradient extension whose intrinsic length scale is calibrated against them. For the effective Young’s modulus, the closed-form expression of Lee et al. reproduces the compression data within 10%, whereas the Tancogne-Dejean and Mohr model remains markedly stiffer even after the strut-level Timoshenko correction is included. In bending, none of the models proves adequate over the full geometric range: the Euler–Bernoulli model is accurate for several configurations (errors below 16% in five of nine cases) but overestimates the stiffness by up to 108% for the deepest specimen; the shear-corrected model reduces the global root mean square error from 97.94 to 24.44 N/mm (approximately a factor of four), but introduces excessive flexibility in some slender and intermediate configurations; and the strain-gradient correction, being strictly stiffening, yields no appreciable improvement. To avoid assigning the discrepancy to a single mechanism, the bending data are further analysed through an experimental compliance decomposition. The additional compliance relative to Euler–Bernoulli theory is small or negative in several cases, showing that shear flexibility alone cannot explain the full dataset, but becomes dominant for the deepest beams. The results therefore delineate the range of validity of simple homogenized beam models for dense finite BCC lattice structures and identify the combined influence of structural shear, non-slender struts, nodal-region morphology, finite-cell and boundary effects, local roller-contact compliance, and the discrete distribution of struts across the cross-section as the main mechanisms requiring more refined descriptions. These findings correspond to a single relative density (${\rho }^{*}\approx 0.423$) and a single strut-to-cell ratio ($R/L=1/6$), so the resulting span-to-depth indicator ($L_0/h\approx 2.5$) should be regarded as indicative for this class of dense lattices rather than as a general design rule. Full article

This paper presents a comprehensive wind tunnel investigation on the wind-induced vibration characteristics of a novel four-cable-supported photovoltaic (PV) structure. The proposed structure system integrates two adjacent dual-cable rows through rigid connecting rods to form a collaborative load-bearing framework, aiming to enhance overall stiffness and mitigate wind-induced vibrations. A 1:15-scale aeroelastic model was tested in a boundary-layer wind tunnel for both single-row and five-row configurations. Wind-induced displacements were measured using a non-contact high-definition camera system capable of real-time, multi-point monitoring across multiple rows, while cable tension forces were simultaneously recorded with load cells—a combined measurement approach rarely reported in existing studies. The effects of wind speed and wind direction angle on the vibration responses were systematically examined. Results reveal that vertical vibrations dominate, with mid-span displacements reaching maximum values. The shielding effect among multiple rows is pronounced: the windward first row consistently exhibits the largest displacements and cable forces under both wind pressure and suction. Wind directions of 0° and 180° are identified as the most unfavorable for pressure and suction, respectively. Cable forces under pressure exceed those under suction, and within each row, windward cables sustain greater forces than leeward cables. These findings provide essential experimental reference data for the wind-resistant design of multi-row cable-supported PV support structures. Full article

Owing to transportation, installation, grid-connection, and maintenance requirements, nearshore offshore wind farms are often located close to busy shipping routes, substantially increasing the risk of ship–offshore wind turbine (OWT) collisions. To enhance the impact resilience of OWT support structures against ship collisions, a novel honeycomb sandwich fender is proposed for tower protection. Nonlinear transient analyses were performed using ANSYS/LS-DYNA to simulate a 5000 t ship traveling at 2 m/s and colliding with a 4 MW OWT supported by a single-column tripod foundation. The effects of rubber and aluminum foam cores on the crashworthiness and protective performance of the fender were compared. The results show that the rubber core stores collision energy through recoverable large deformation and releases most of the stored energy during unloading, resulting in pronounced energy restitution and prolonged structural excitation. By contrast, the aluminum foam core dissipates 7.5 MJ through cell-wall buckling, progressive crushing, and plastic collapse, corresponding to 75% of the initial kinetic energy of the ship. Compared with the rubber-core fender, the higher initial stiffness of the aluminum foam increases the peak contact force by 23.1%, from 13.0 to 16.0 MN. However, its irreversible energy-dissipation mechanism reduces the maximum tower-top displacement by 40.0%, from 1.25 to 0.75 m, and decreases the residual tower stress after three successive collisions by 25.0%, from 200 to 150 MPa. These results demonstrate that, despite transmitting a higher peak contact force, the aluminum foam fender provides more effective overall protection under the collision conditions considered because of its greater irreversible energy-dissipation capacity. Full article

The extracellular matrix (ECM) in cancer differs from healthy tissue in structure, composition, and mechanical properties. Matricellular proteins (MCPs) play important roles in shaping ECM architecture during tissue remodeling. This narrative review, combined with a bioinformatics analysis, examines six major MCP families—Fasciclins, Tenascins, Thrombospondins, Small Leucine-Rich Proteoglycans, the SPARC family, and the CCN family—through a mechanobiological lens in bladder cancer. It summarizes current knowledge on the mechanical regulation of MCP expression, their effects on matrix stiffness, and their contributions to bladder cancer progression. Analyses of public datasets reveal that stromal cells are the predominant source of MCPs in the tumor microenvironment. Furthermore, mechanical upregulation and involvement in the formation of stiff ECM highlight MCPs as important players in a mechanotransduction feedback loop. While most MCPs exert pro-tumorigenic effects on bladder cancer cells, several display context-dependent or anti-tumorigenic activities. Existing studies have primarily focused on the isolated effects of MCPs on bladder cancer cell lines in two-dimensional systems or simple subcutaneous xenograft models. Both approaches fail to capture the context-dependent nature of MCPs and their involvement in ECM formation. These findings underscore the need for future studies to investigate the complex effects of MCPs on bladder cancer progression. Full article

Cardiovascular diseases (CVDs) remain a leading cause of mortality worldwide, and ageing is strongly associated with progressive arterial stiffening. Age-related alterations in extracellular matrix (ECM) mechanics influence vascular smooth muscle cell (VSMC) behaviour, while sympathetic innervation represents an additional regulator of vascular homeostasis. However, how neural signalling interacts with ageing-associated mechanical conditions to regulate VSMC behaviour remains unclear. In this study, an in vitro sympathetic neuron–VSMC co-culture model was established to investigate neuro-mechanical regulation. Primary rat sympathetic neurons and A7r5 VSMCs were cultured on glass or polydimethylsiloxane (PDMS) substrates with defined stiffness (20 and 130 kPa), representing healthy and ageing-associated stiffened arterial environments, respectively. VSMC behaviour was assessed through analysis of cell area, proliferation, migration, cellular Young’s modulus (YM), and DNA damage marker γH2AX. Sympathetic neuronal co-culture was associated with reduced VSMC spreading and decreased γH2AX levels. Under the conditions tested, neural signalling exerted limited effects on cell proliferation and migration. In contrast, increased substrate stiffness promoted cell proliferation and elevated YM. Both neuronal input and substrate stiffness were associated with increased cellular YM. Together, these findings indicate that neural and mechanical cues may jointly influence VSMC behaviour within ageing-associated mechanical environments. This co-culture system provides a controllable platform for studying neuro-mechanical interactions in vascular biology. Full article

Proteinase-activated receptor 2 is a G protein-coupled receptor that regulates vascular tone and inflammatory signalling in the circulatory system. The roles of PAR2 appear complex and sometimes opposing. Studies using PAR2-deficient mice provide a framework to define these effects at the system level. This review examines cardiovascular phenotypes associated with PAR2 deficiency in basal conditions and in disease. PAR2 deficiency produces modest increases in arterial blood pressure and vascular stiffness while preserving endothelial vasodilator function. Cardiac function remains largely normal in young PAR2-deficient animals but changes with age. Older PAR2-deficient mice develop diastolic dysfunction and cardiac fibrosis. In disease models, PAR2 deficiency has been associated with increased fibrosis in cardiac and vascular tissues and reduced vascular inflammation in atherosclerosis. PAR2 deficiency is also associated with reduced plaque progression and features of plaque stabilisation. In myocardial ischaemia models, PAR2 deficiency has been associated with reduced cardiac injury and adverse remodelling. The effects of PAR2 deficiency on inflammatory signalling vary according to tissue and disease context. Together, these findings suggest that the cardiovascular consequences of PAR2 deficiency depend on physiological and pathological context. Future studies should define cell-specific mechanisms to guide therapeutic targeting of PAR2. Full article

The effects of an external electric field (EEF) on the crystal structure, nonbonded interaction, sensitivity, and mechanical properties of CL-20/H₂O₂ and CL-20/H₂O energetic solvates have been investigated by classical molecular dynamics simulations. Compared with CL-20/H₂O solvate, CL-20/H₂O₂ solvate possesses stronger O-H···O and C-H···O hydrogen-bond networks, which are more sensitive to the variation of electric field intensity. Such hydrogen-bond frameworks buffer the fluctuation of cell parameters and restrain molecular diffusion under an EEF. Increasing the electric field shortens the N-NO₂ trigger bond and reduces its interaction energy, strengthening the intrinsic sensitivity of CL-20 solvates. The conformers of CL-20 molecules transform from the α-phase to the stable ε phase after 0.4 V·Å⁻¹. When an external electric field acts on the CL-20/H₂O₂ and CL-20/H₂O energetic solvates, conformational changes in CL-20 molecules and solvation interactions can effectively reduce stiffness and enhance lattice ductility, reducing hotspot formation and thereby improving thermal safety. Full article

Cartilage regeneration remains a major clinical challenge because cartilage has limited healing capacity and must withstand substantial mechanical loading. Silk fibroin, a cocoon-derived biomaterial with tunable mechanical properties, has emerged as a promising scaffold material for cartilage tissue engineering. This systematic review evaluates the biomechanical performance, fabrication approaches, and regenerative potential of silk fibroin bioprinted scaffolds for cartilage repair. A systematic review was conducted according to PRISMA guidelines. Primary outcomes included scaffold mechanical properties relevant to cartilage function. Secondary outcomes included scaffold composition, fabrication methods, biological performance, clinical applications, and reported limitations. Of 918 identified records, 24 studies published between 2014 and 2025 met the inclusion criteria. Most were preclinical studies using silk fibroin-based hydrogels, often combined with hyaluronic acid, gelatin, collagen, or synthetic polymers. Mechanical properties varied according to scaffold composition and crosslinking methods. Reinforced scaffolds generally demonstrated improved stiffness, structural support, and load distribution. Silk fibroin scaffolds consistently supported chondrogenesis and cartilage-like tissue formation. However, challenges remain, including mechanical mismatch with native cartilage, construct instability, cell loss, and suboptimal degradation profiles. Overall, silk fibroin bioprinted scaffolds demonstrated support for chondrogenesis and cartilage-like tissue formation in preclinical studies for cartilage regeneration. Future research should focus on standardized biomechanical testing, long-term in vivo evaluation, and clinically relevant scaffold designs to facilitate translation toward functional cartilage repair. Full article

The paradigm of craniomaxillofacial (CMF) reconstruction is shifting from traditional bone grafting and biochemical adjuncts toward a nucleomechanical framework that leverages the cell nucleus as a mechanosensitive organelle. By utilizing computer-aided design and computer-aided manufacturing (CAD/CAM)-derived scaffolds with 10 µm micropillar arrays and specific interfacial stiffness (25–40 kPa), surgeons can physically manipulate the Linker of Nucleoskeleton and Cytoskeleton (LINC) complex to achieve a nuclear aspect ratio above 2.5. This structural deformation mechanically expands nuclear pores to trigger cytoskeletal and molecular responses, such as Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) translocation. Resultantly, this physical tension pulls open chromatin fibers to activate master osteogenic regulators like RUNX2, effectively bypassing the risks and limitations associated with supraphysiologic growth factor delivery (e.g., rhBMP-2). Clinically, translating these principles involves moving away from absolute rigid internal fixation toward advanced resorbable biomaterials that permit controlled micro-motions (100–200 µm) under functional masticatory loads. This review provides a structured synthesis of the field, outlining deterministic topographic criteria, clinical boundary conditions, and the potential strategies needed to overcome age-related mechanosensory blockades. Ultimately, we establish a multidisciplinary framework that bridges precision bioengineering with native oral and maxillofacial surgical realities to drive living, biophysically mediated bone repair. Full article

Contact-surface construction affects pressure distribution, physiological response, and perceived comfort in body-contact furniture. This study compared five contact interfaces for classroom nap chairs: rigid polypropylene (PP), a thermoplastic polyurethane (TPU)-surfaced PP laminate, woven mesh, closed-cell ethylene-vinyl acetate (EVA) foam, and flexible polyurethane (PU) foam. Twenty-six participants, including 13 females and 13 males, were tested in a 95° study posture and a 135° nap posture at the head–neck, waist–back, and hip–thigh regions. Four participant-level pressure indicators were direction-corrected and combined using an equal-weight geometric mean. The pressure index was integrated with electrodermal activity (EDA) at the participant level and subsequently combined across postures with weak subjective calibration. Under the 95° posture, EVA foam ranked highest at the hip–thigh region, while PU foam ranked highest at the waist–back and head–neck regions. Under the 135° posture, woven mesh ranked highest at the hip–thigh and head–neck regions, while PU foam remained highest at the waist–back region. Final integrated suitability differed significantly among materials in all three body regions (Friedman χ² (4) = 90.246–96.769, all p < 0.001). M4 had the highest mean in the head–neck region (0.648), but did not differ significantly from M5 (0.634; Holm-adjusted p = 0.075). M5 had the highest mean in the waist–back region (0.821), and M3 in the hip–thigh region (0.679); both were significantly higher than the corresponding second-ranked interfaces (Holm-adjusted p < 0.001). Exploratory stiffness models indicated peak locations near 130 kPa for the head–neck region and 140 kPa for the hip–thigh region, whereas the waist–back response was highest at the lower measured boundary of 70 kPa. These findings support region-specific interface design rather than a uniform contact surface for the entire chair. Full article