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This study evaluated the ability of older caregivers (aged &#x2265;75&#x2009;years) to operate a manual wheelchair across environmental barriers and examined associations with physical function. Fifty-six women participated, including 36 older adults (aged &#x2265;75&#x2009;years) and 20 younger adults. Physical function was assessed using grip strength, mobility, balance, and locomotive syndrome (LS) stage. Wheelchair-operating ability was evaluated across level and uneven terrains-specifically through slope ascent, side-slope navigation, front-caster lifting, and wheel-recovery tasks-while participants pushed a manual wheelchair loaded with a 60-kg dummy. Compared with younger adults, older adults showed poorer physical function and wheelchair-operating performance across most tasks. Notably, 22.2% of older adults could not lift the front casters over a 10-cm step. Among older adults, a higher LS stage independently correlated with poorer wheelchair-operating performance during normal-speed slope ascent (&#x3b2;&#x2009;=&#x2009;0.474, p&#x2009;=&#x2009;0.002), fast slope ascent (&#x3b2;&#x2009;=&#x2009;0.317, p&#x2009;=&#x2009;0.030), and fast side-slope navigation (&#x3b2;&#x2009;=&#x2009;0.579, p&#x2009;<&#x2009;0.001). Furthermore, weaker left-hand grip strength was associated with poorer slope-ascent performance at both normal (&#x3b2; = -0.357, p&#x2009;=&#x2009;0.014, adjusted R2 = 0.48) and fast speed (&#x3b2; = -0.413, p&#x2009;=&#x2009;0.004, adjusted R2 = 0.53). Conversely, no physical function variables significantly predicted performance during the front-caster lifting or wheel-recovery tasks. Age-related declines in mobility and upper-limb strength may compromise wheelchair-operating safety. Targeted training, instruction, assistive technologies, and ergonomic wheelchair designs may improve safety and mobility. Barrier-free environments also remain essential for supporting community participation in ageing societies. Assistive product development with user-friendly features and the widespread implementation of barrier-free environments can gradually facilitate safe outings.To enable older caregivers to safely operate wheelchairs and participate in community activities, physiotherapists and allied health professionals must help maintain and enhance the caregivers&#x2019; physical function and provide comprehensive operational training.Because steep slope gradients and elevated steps pose significant hazards to older caregivers, urban planners and rehabilitation professionals must collaborate to design accessible, wheelchair-friendly public infrastructure.

Physical activity offers myriad benefits to health and well-being, in humans and other animals as well. In rodents, voluntary wheel running can attenuate the effects of both physical and social stressors on rodent social behavior. Whether wheel running affects rodent social behaviors per se remains less well understood. We conducted the current study to test whether home cage access to running wheels impacts the social behaviors of adult, group-housed C57BL/6J female mice during same-sex interactions with novel females. Group-housed females were either given continuous home cage running wheel access or a standard paper hut starting at weaning, and as adults, social behaviors were measured during interactions with novel females. In two cohorts, we found that 5 weeks of running wheel access during adolescence reduced the time that subject females spent investigating a novel female and also tended to reduce total ultrasonic vocalizations produced during interactions. These effects were not reversed by a 2-week period of running wheel removal but were recapitulated in a different cohort by 2 weeks of running wheel access in adulthood. Unexpectedly, we found that these effects on female social behavior were not due to wheel running per se, because females raised from weaning with 'immobile' running wheels also showed low rates of social behaviors during same-sex interactions in adulthood. Overall, we find that the presence of a running wheel in the home cage has an enduring inhibitory influence on female social behavior during same-sex interactions, a finding that has implications for the design of studies that include same-sex interactions between female mice.

This study investigated differences in biophysiological strain across six levels of pushrim-activated power-assisted wheelchair (PAPAW) support. Fourteen experienced wheelchair users (mean age 42.2&#x2009;&#xb1;&#x2009;14.0&#x2009;years) performed six 4-minute submaximal propulsion trials at a fixed speed (0.56, 0.83, or 1.11&#x2009;m/s) and resistance (0.21&#x2009;W/kg body mass). Each trial used a different assistance level, none, very low, low, medium, high, and very high, in counterbalanced order. Physiological strain was assessed via energy expenditure, heart rate, and perceived exertion. Biomechanical parameters, including work per push and propulsion forces, were derived from a force-instrumented wheelchair ergometer. Generalised Linear Mixed Models revealed that increased assistance level significantly reduce metabolic outcomes, including energy expenditure and heart rate (p&#x2009;&#x2264;&#x2009;0.001). Kinetic and temporospatial variables such as mean and peak push forces, work per push, contact angle and push time also significantly decreased with higher assistance (p&#x2009;&#x2264;&#x2009;0.016). Movement variability and asymmetry increased during higher assistance levels (p&#x2009;=&#x2009;0.002). Increasing PAPAW assistance resulted in an incremental reduction in both physiological and biomechanical strain in wheelchair users. The results might be used to tailor the correct amount of support to individual needs. Future research should aim to identify optimal balance, one that alleviates physical strain without compromising the user's overall fitness.Implications for RehabilitationHigher assistance levels of Pushrim-Activated Power-Assisted wheels lead to reductions in physiological demands and decreased push forces, work per push, contact angle and push time. Confirming that an increased level of assistance decreases the biophysical strain of manual wheelchair propulsion.Yet, propulsion with Pushrim-Activated Power-Assisted wheels causes a movement variability and asymmetry compared to unassisted manual wheelchair propulsion, which may have implications for driving behaviour and control.

In satellite-denied environments such as urban canyons, tunnels, and underground parking facilities, achieving high-precision autonomous positioning for vehicles remains a critical challenge. Although high-precision inertial measurement units (IMUs) can provide accurate dead reckoning, their deployment is limited by cost, size, and power consumption, making low-cost, microelectromechanical systems IMUs (MIMUs) an attractive alternative solution. However, the single MIMU suffers from substantial measurement noise and bias instability, leading to rapid error divergence that cannot sustain long-term autonomous navigation. To address the above issues, this paper proposes an autonomous positioning system based on a wheel-mounted MIMU array (Wheel-AINS). The system adopts a differential layout in which multiple low-cost MIMU chips are installed at the center of each of the left and right rear wheels, forming redundant sensor arrays. By differentially fusing symmetrically mounted chips, common-mode noise and zero bias are effectively canceled while the wheel rotation provides natural rotational modulation. The fused gyroscope outputs and known wheel radius are then used to estimate the vehicle forward speed, replacing traditional odometers. The estimated wheel speed and vehicle kinematic constraints are then integrated within a Kalman filter framework to suppress the error divergence of the inertial navigation system. A dedicated embedded hardware prototype with multi-chip synchronous acquisition and wireless transmission was developed. Three groups of urban road tests with total distances of 0.85 km, 2.14 km, and 2.49 km were conducted. The results indicate that the average position drift rate of the Wheel-AINS is 0.50%, and the average heading RMSE is 12.2&#xb0;. The closure error of the 2.49 km trajectory is 10.43 m, reduced by approximately 80% compared with a single MIMU. The ablation experiment reveals that the MIMU array fusion module is the primary source of accuracy improvement, reducing the position RMSE from 155.0 m to 10.1 m, while the dual-wheel distance constraint further optimizes the position RMSE to 8.2 m, but increases the heading RMSE from 13.3&#xb0; to 13.6&#xb0;. This demonstrates that the proposed method can substantially improve autonomous positioning accuracy while maintaining a notably low system cost, providing a viable technical pathway for long-endurance vehicle navigation in satellite-denied environments.

Driven by the automotive industry's strategies for energy conservation, emission reduction, and lightweighting, magnesium alloy wheels have emerged as a key focus of research and industrialization efforts, owing to their high specific strength, excellent vibration-damping properties, and superior heat dissipation performance. This paper provides a systematic review of the performance advantages, material systems, forming processes, applications, and industrialization challenges of magnesium alloy automotive wheels. The core advantages of magnesium alloy wheels in terms of weight reduction, vibration damping, and thermal management are elaborated. The compositional characteristics, suitable processes, and performance differences between cast magnesium alloys (e.g., AZ91D, AM60B) and wrought magnesium alloys (e.g., AZ80, ZK61-Y) are outlined. The technical characteristics, microstructural and property evolution, and limitations of casting processes (gravity, high-pressure, low-pressure, and semi-solid casting), plastic forming processes (isothermal extrusion forging, backward extrusion forging, and spin forming), and hybrid processes are discussed. Combined with the case studies of magnesium alloy wheel applications in the automotive sector, this paper analyzes the core bottlenecks of magnesium alloy wheels in terms of corrosion resistance, production cost, and industrial consistency, and outlines future research directions. This paper aims to provide theoretical references and technical support for the design, manufacturing, and large-scale application of lightweight, high-performance magnesium alloy wheels.

This study examines the applicability of Plasma Transferred Arc (PTA) surface treatment as an advanced technique for the refurbishment of railway wheel treads. Conventional wheel reprofiling, typically performed on semi-automatic lathes, requires the removal of a minimum of 6 mm of material from the running surface, which accelerates rim thinning and ultimately necessitates wheel replacement. Moreover, the reprofiled surfaces are not subjected to any subsequent treatment aimed at enhancing their durability. To overcome these limitations, PTA cladding was selected due to its ability to generate surface layers with superior mechanical and tribological properties. In contrast to widely used diode laser technologies, PTA enables the deposition of alloying materials in powder form, ensuring a stable, controllable, and efficient cladding process. The resulting microstructure consists of a heat-affected zone, a transition zone, and a re-melted zone, each exhibiting significantly increased hardness relative to the untreated base material. The process facilitates the incorporation of metallic particles into the surface layer, promoting the formation of a dense, wear-resistant coating. These materials possess huge potential utility regarding the wear resistance reaching even ca 10% of the base material wear in the case of 505 PTA and over 20% in the case of the 15 E material. The findings indicate that PTA surface treatment has substantial potential to extend the operational lifespan of railway wheels by providing a highly durable and mechanically robust surface, thereby reducing maintenance frequency and the associated costs.

To address the inefficiency of demolition robots at nuclear contamination sites due to frequent retreats to safe zones for attachment replacement, this study develops and experimentally evaluates a six-wheeled mobile platform for attachment-replacement support near the work area. Structurally, the prototype adopts a well-established passive rocker-bogie suspension architecture combined with six-wheel independent drive. The focus of this work is not to claim a new suspension topology, but to evaluate its engineering feasibility and drive-load margins for a heavy-duty nuclear support platform through multibody simulation and onboard-sensor measurements. A constrained multibody model was implemented in ADAMS/Simulink to represent rocker joints, wheel revolute joints, actuator limits, and wheel-ground contact. A full-scale prototype was tested on representative nuclear-facility terrain conditions, including a 20&#xb0; slope and a 250 mm vertical step. The results show that the prototype completed both tests while the measured motor torques remained within the allowable drive range. The positive and negative torque signs observed on the left and right sides are explained by mirrored motor installation and coordinate definitions rather than by a special torque-distribution mechanism. This study provides a structural selection and experimental performance reference for mobile operation support in radiation environments.

Exercise modulates multiple physiological systems, including skeletal muscle and the gut microbiome (GMB). Ammonia, a microbiome-derived cytotoxic metabolite, causes cellular hyperammonemic stress (HAS) in chronic diseases. We investigated the impact of voluntary wheel running (VWR) on GMB during HAS in a mouse model. Male C57BL/6J mice were randomized to treatment with either ammonium acetate (AmAc) (2.5 mmol/kg/day) or vehicle for 6 weeks. Stool 16S rRNA sequencing was performed at baseline, pre-intervention, and post-intervention. GMB diversity, taxa-level abundance, and correlation analyses were performed. Overall GMB composition remained stable between baseline and pre-intervention across groups (r > 0.57; P < 0.001). Following interventions, VWR or usual activity (UA), alpha-diversity was highest in AmAc-treated, specifically AmAc-VWR, mice. Eubacterium xylanophilum was reduced in AmAc-UA vs other groups (P < 0.05). Akkermansia abundance declined over time in UA mice, but in AmAc-VWR mice, this depletion was reversed (P = 0.002). Clostridium sensu stricto 1 and Eubacterium ventriosum were increased in AmAc-VWR mice (P < 0.05). Correlation analysis revealed high stability in PBS-UA (r = 0.667; P < 0.001), moderate restructuring in AmAc-VWR (r = 0.566; P < 0.001), and PBS-VWR (r = 0.385; P = 0.0099). HAS-induced GMB instability, with loss of beneficial taxa, including short-chain fatty acid-producing bacteria, was partially ameliorated by VWR. Exercise-mediated GMB modulation may be a strategy to mitigate HAS-induced complications in chronic diseases.IMPORTANCEVoluntary exercise is recommended in chronic diseases to improve outcomes, but biological responses in disease are not well characterized. Perturbations in the metabolism of ammonia, a microbiome-generated toxin, occur in chronic diseases that can be compounded by muscle-generated ammonia during exercise. Exercise-induced molecular responses are adversely affected by hyperammonemic stress of chronic diseases, including liver cirrhosis. We investigated gut microbiome changes during voluntary wheel running, which replicates human endurance exercise in a preclinical mouse model of hyperammonemia. Adverse impacts of Hyperammonemic stress included a reduction in short-chain fatty acid producers that were reversed by voluntary wheel running. Our data lay the foundation for future studies on how endurance-type exercise promotes a favorable gut microbial composition and strategies to use exercise as a regulator of hyperammonemic stress via targeting the gut microbiome.

Pearlitic wheel steel subjected to thermal-mechanical fatigue (TMF) during braking can undergo catastrophic fracture. This study clarifies the microstructural evolution governing the macroscopic cyclic hardening/softening behavior of pearlitic wheel steel under thermal-mechanical fatigue (TMF) with a constant mechanical strain range of -0.4% to +0.2%. At lower temperature amplitudes (200-500 &#xb0;C), the geometrically necessary dislocation (GND) density reaches 20.4 &#xd7; 1014/m2 during initial cycles, corresponding to cyclic hardening due to dislocation pile-ups at cementite lamellae interfaces. With increasing cycles, the GND density decreases to 12.3 &#xd7; 1014/m2, concurrent with softening arising from lamellar bending/fracture, partial spheroidization, and dynamic recrystallization of ferrite. At higher temperature amplitudes (200-730 &#xb0;C), the GND density decreases from 8.8 &#xd7; 1014/m2 to 3.5 &#xd7; 1014/m2, reflecting sustained cyclic softening dominated by thermally activated mechanisms, including cementite spheroidization and dislocation annihilation. The resulting softened microstructure consists of ferrite grains, intragranular dispersed cementite, and chain-like coarse cementite at boundaries. Unlike previous studies that focused on single loading conditions (e.g., thermal fatigue, rolling contact fatigue, or wear), the present work addresses the more complex TMF scenario and quantitatively elucidates the interplay between mechanical response and microstructural evolution in pearlitic steel. This work provides theoretical guidance for the development of a fatigue life prediction model for pearlitic wheels under braking.

Field-based performance and skill tests are widely used in wheelchair rugby (WR) to assess physical capacity, yet their relation to in-game mobility and potential differences between athletes with and without coordination impairment (CI) remain unclear. This study examined (1) ecological validity and test-match correspondence of a comprehensive WR field-test battery, reflecting maximal capacity, against match-derived mobility performance, (2) impairment-based differences in test-match agreement, and (3) trunk-movement differences between CI and Non-CI athletes. Fifty-two international WR athletes (Non-CI: n&#x2009;=&#x2009;27; CI: n&#x2009;=&#x2009;25) completed a standardized battery (sprint, turning, stop-go, complex skills) with wheel- and trunk-mounted inertial sensors. Match metrics (e.g., average/maximal speed, rotational speed) were derived from full-match IMU data. Test-match correspondence was assessed using Pearson correlations and Lin's concordance; agreement with Bland-Altman analysis; group differences with Welch's t-tests (FDR/Holm corrected). Trunk angle and trunk-relative accelerations were analyzed separately, with classification included in supplementary analyses. Maximal forward speed showed strong association (20&#x2005;m sprint: r&#x2009;=&#x2009;0.878, small bias), and rotational capacity was best captured by an isolated 180&#xb0; turn (r&#x2009;=&#x2009;0.796). Acceleration metrics showed moderate correlations but poor absolute agreement, indicating they reflect maximal capacity rather than match-equivalent output. CI athletes showed smaller test-match discrepancies, whereas Non-CI athletes' tests tended to underestimate match speed and overestimate acceleration. Trunk-sensor outcomes differed strongly between groups (g&#x2009;&#x2248;&#x2009;0.9-1.2), indicating substantial impairment-related variation. Classification correlated positively with performance, with similar strength across groups. Linear sprint and isolated turning tests show strong associations with in-game WR performance, while acceleration metrics mainly index maximal capacity. Field tests appear to align more closely with match behavior in CI athletes than in Non-CI athletes. Trunk-sensor measures add value for profiling and may support future classification.

To address the problem of high-frequency roll disturbances generated during dynamic balancing in non-coaxial two-wheeled robots, this paper proposes a Rotation-Optimized Inertial-Visual SLAM system (ROIV-SLAM) for robust state estimation. The proposed approach adopts a decoupled architecture for translation and rotation estimation. In the front-end, an Extended Kalman Filter (EKF) is employed to fuse LiDAR, an inertial measurement unit (IMU), and wheel odometry to obtain an initial translation estimate. Meanwhile, a physical manifold constraint is constructed using the gravity vector and surface normals extracted from RGB-D point clouds, supporting stable rotation estimation under high-frequency disturbances through Lie-group-based optimization. In the back-end, a factor graph is established, and loop closure robustness is enhanced through vision-LiDAR scan matching. Experimental results indicate that ROIV-SLAM achieves improved trajectory consistency with respect to the optimized reference trajectory and more robust mapping performance compared with the evaluated baseline approaches in the tested scenarios. The results further suggest that introducing task-specific physical dynamic constraints and a decoupled estimation mechanism helps suppress high-frequency motion noise inherent to balancing robots, thereby improving the robustness of state estimation in complex environments.

AI has entered the wellness space through apps and wearables. These technologies can collect real-time data, infer lifestyle patterns, and dynamically generate nutrition and exercise recommendations. Generative AI personalizes diet and activity information, encouraging behavior change. The objective of this Viewpoint is to explore the potential medium-term consequences of AI integration in diet and exercise apps from an end-user perspective. We applied a foresight methodology-the Futures Wheel (FW)-and defined its central trend as the growing integration of AI into consumer wellness platforms. The analysis outlines seven first-order consequences: (1) personalization of nutrition and fitness plans, (2) 24/7 health coaching, (3) integration with smart technology, (4) increased privacy and surveillance concerns, (5) data-driven risk profiling and moral hazard, (6) incorporation into organizational processes, and (7) acceleration of health inequalities driven by the digital divide. Second-order consequences included potential improvements in health outcomes and health literacy, as well as risks of privacy erosion, algorithmic bias, behavior-linked underwriting models, deskilling of health and fitness professionals, and shifts in food and exercise culture toward more individualized, and potentially isolating practices. Cross-cutting patterns highlighted recurring trade-offs between personalization and surveillance, scalability and user agency, and optimization and equity. Wellness practice will expand along with AI's ability to personalize recommendations, automate behaviors, and engage users. AI wellness popularization is promising for chronic disease prevention and health optimization. The FW reveals that the depth of adaptation will be determined by the implementation of changes at the levels of technology, user behavior, infrastructure, and legal and ethical frameworks.

Background: Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most prevalent neurodevelopmental disorders among children and is associated with significant behavioral, academic, and social challenges. Caregiver-focused behavioral interventions have gained increasing attention as effective non-pharmacological approaches for improving child outcomes and enhancing parental management skills. Thus, this study aimed to evaluate the potential effectiveness of behavior change wheel (BCW)-based nursing intervention in improving maternal behavioral management practices, as well as child outcomes involving ADHD symptoms among preschool children aged 3-6 years with attention-deficit/hyperactivity disorder. Methods: A one-group pretest-posttest quasi-experimental design was conducted among 55 mothers and their children diagnosed with ADHD at Thawat Center and King Abdullah Center for Disability Services in Jeddah, Saudi Arabia. The study did not include a control group. Participants were recruited using a convenience sampling technique. Data were collected using a sociodemographic questionnaire, ADHD Rating Scale IV-Preschool Version, the BCW Intervention Compliance Questionnaire, and the Parental Knowledge and Attitude Questionnaire. The intervention was implemented over eight weeks and included educational sessions, behavioral skills training, motivational enhancement, role-play activities, and follow-up reinforcement. Results: The preliminary findings from the one-group pre/posttest quasi-experimental study revealed statistically significant improvements in children's inattentive and hyperactivity symptoms following the intervention (p < 0.001). Mothers also demonstrated significant improvements in perceived knowledge, attitudes, and compliance with BCW components after program implementation (p < 0.001). The proportion of mothers with satisfactory perceived knowledge increased from 21.8% pre-intervention to 94.5% post-intervention, while positive attitudes increased from 23.6% to 98.2%. In addition, compliance with BCW components improved from 30.9% before the intervention to 94.5% after implementation. Conclusions: The BCW-based nursing intervention was associated with pre-post improvement in maternal caregiving outcomes and reduced ADHD symptoms among preschool children. These preliminary findings from the one-group pretest-posttest quasi-experimental study suggest the potential value of theory-informed, caregiver-focused nursing interventions in pediatric and community healthcare settings. However, due to the one-group pretest-posttest design without a control group, causal inferences cannot be made. Further controlled studies are needed to confirm these associations and establish causal inferences.

This study proposes an integrated fault estimation and fault-tolerant control strategy for actuators of four-wheel independently driven vehicles. Firstly, a modeling approach is developed by combining the vehicle dynamics model with the steering actuator model to establish a system model in the presence of actuator faults. Subsequently, to simultaneously estimate the system states and actuator faults, an unknown input observer (UIO) is designed, treating actuator faults as unknown state variables and augmenting the system state variables to achieve simultaneous estimation of states and faults, providing a foundation for subsequent fault-tolerant control research. The gain matrices of the fault observer and the fault-tolerant controller are both obtained through single-step linear matrix inequality (LMI) computations, realizing the design of an integrated fault-tolerant control system. Finally, the effectiveness and superiority of the proposed method are verified through hardware-in-the-loop experimental tests.

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This study examines enablers and barriers to integrating biological maturation into talent identification and development processes within German football academies. Biological maturation significantly influences physical performance, selection decisions, and injury risk in youth football. Early maturing players are often favoured during talent identification, leading to premature deselection of talented late-maturing athletes. Using the COM-B framework (Capability, Opportunity, Motivation - Behaviour), we investigated stakeholders perceived barriers and enablers to implementing maturation strategies. An adapted COM-B-Qv1 questionnaire was distributed to 990 stakeholders across 56 elite academies and 344 regional training centres (June - July 2025), yielding 142 complete responses (14.3% completion rate). Internal consistency of the adapted scales was acceptable to good (Cronbach's &#x3b1;&#x2009;=&#x2009;0.67-0.84). Results showed that 78% of participants conduct maturation assessments, while 24% rarely or never considered it in player development and 51% did so only occasionally. Regional-affiliated stakeholders reported significantly higher barriers than league-affiliated participants (p&#x2009;<&#x2009;0.05). Opportunity, expressed through the perceived lack of tools, time, and incentives, emerged as the strongest barrier (mean&#x2009;=&#x2009;3.38&#x2009;&#xb1;&#x2009;1.30). These findings suggest that targeted training, enablement, and environmental restructuring may be particularly effective for improving the systematic integration of biological maturation in German football academies, especially in regional settings.