Reconfigurable mechanical systems enable precise programmable control over structural properties, expanding opportunities in architected materials, adaptive devices, and multifunctional structures. Here, we introduce elastic rod origami (RodOri), a platform that exploits remarkably simple elements-prestressed, naturally curved rods-into a system with an extraordinary degree of multistability and configurational richness. For example, a single six-rod RodOri unit can easily access 11 distinct configurations, far exceeding the reconfigurability of conventional origami or general mechanical reconfigurable systems. Individual rods, constrained under clamped boundary conditions, undergo transitions between discrete morphologies whose strain energy and stiffness are precisely prescribed by their natural curvature. Assembling these rods into modular multirod architectures yields metamaterials with numerous stable configurations that can be selectively and reversibly programmed. This configurational diversity enables tunable static stiffness and nonlinear force response, thus enabling tunable dynamic behaviors such as vibration filtering, wave propagation switching, and mode conversion within a single, easily manufactured platform. By leveraging curvature-induced mechanical instability, RodOri unlocks highly programmable static and dynamic mechanical behavior, offering tailorable design strategies for reconfigurable structures, soft robotics, medical devices, and adaptive materials.

Cell behaviors in multicellular organisms are coordinated via both diffusible molecules and by signals based on direct cell-cell contacts. The mode of cell communication used influences the signaling range. In many developing epithelia, contact-based Notch-Delta lateral inhibition signaling is used to pattern cell fates. While previous work revealed that cells can use protrusions to extend the range of Notch-Delta signaling to alter these patterns, this is not a general feature of epithelia. In addition, it is not known how the complex three-dimensional (3D) shapes of epithelial cells influence cell communication. In exploring this question, we show that epithelial cells at the Drosophila wing margin, which lack basal protrusions, contact different neighbors at different heights along their apico-basal axis, effectively increasing the number of neighbors each cell touches. To quantitatively assess this behavior, we develop a mathematical modeling framework (Multilayer Signaling Model) to simulate Notch-Delta signaling over data-derived 3D cell topologies. The model predicts that lateral cell surface signaling is essential to tune the spacing between sensory organ precursors (SOPs). In agreement, we show that perturbing cortical stiffness and cell tortuosity in vivo modifies SOP spacing. These results emphasize the importance of 3D cell geometry and topology in fine-tuning signaling range.

Because male physiology was historically viewed as the "norm" and data on females were considered difficult to interpret, little information regarding the effects of regular exercise on women's health over the lifespan was available leading into the 1990s. In 1993, we initiated research at the University of Colorado Boulder to determine the effects of endurance exercise training on healthy cardiovascular aging in women. To do so, we used a "masters athlete model" in which midlife and older female distance runners were compared with their healthy, but non-exercising peers, as well as young adult women. The masters runners (~50-70 years, mostly postmenopausal) had a maximal oxygen consumption (V̇O2max) almost twice that of non-exercising postmenopausal women, in part due to a larger total blood volume. The masters runners showed stable body mass with age/menopause and exhibited much smaller age-related differences in total body fatness and abdominal adiposity than non-exercising women, related in part to preserved resting metabolic rate. The masters runners maintained a healthier overall systolic blood pressure profile and showed smaller differences in large elastic artery (aorta and carotid arteries) stiffness with age/menopause compared with non-exercising women. In contrast to non-exercising women, circulating coagulation and fibrinolytic activity was well-preserved with age/menopause in the masters runners. Masters runners also maintained greater heart rate variability, more favorable regulation of plasma glucose and insulin, and a superior plasma lipid-lipoprotein profile compared with non-exercising postmenopausal women. In contrast to males, female masters athletes did not demonstrate greater vascular endothelial function than their non-exercising peers. Collectively, this work represented the first systematic research conducted on the benefits of endurance exercise training on optimal cardiovascular function and health with age/menopause in women using the masters athlete model.

Women's cardiovascular disease risk increases during midlife, in part, due to accelerated vascular dysfunction. Age-related vascular dysfunction includes increases in large artery stiffness, which may be mitigated by maintaining muscular strength. However, the relationship between handgrip strength and large artery stiffness through the lifespan in women is unknown. PURPOSE: Evaluate the relationship between handgrip strength and large artery stiffness in women. METHODS: Maximal handgrip strength relative to body weight (MVC/BW), carotid artery stiffness (β-stiffness), and aortic stiffness (carotid-femoral pulse wave velocity [cfPWV]) were measured in 216 women (n=54 young 29±9yrs, n=73 middle-aged 56±6yrs, n=89 older 72±6yrs). Multivariate linear regression was employed to evaluate the relationship between large artery stiffness and MVC/BW, age, and the MVC/BW by age interaction while adjusting for potential confounders. RESULTS: In the fully adjusted model, age [B=0.23 (95% CI, 0.12, 0.35), p<0.001] and the age by MVC/BW interaction [B=-0.28 (-0.55, -0.02), p=0.04] were associated with β-stiffness. Similar results were observed with cfPWV [Age: B=0.15 (0.09, 0.20), p<0.001; AgexMVC/BW: B=-0.15 (0.28, -0.02), p=0.02], which remained after further adjustment for mean arterial pressure. Simple slope analyses revealed inverse associations between MVC/BW and cfPWV (p=0.02) and β-stiffness (p=0.07) among older women, with weak to no associations observed among young or middle-aged women (p=0.19-0.75). CONCLUSION: Age modifies the relationship between relative handgrip strength and large artery stiffness in women. The direction of the relationship between relative handgrip strength and large artery stiffness changes across the lifespan in women, with greater handgrip strength being associated with lower large artery stiffness after middle-age.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a progressive condition linked to obesity and insulin resistance, potentially leading to cirrhosis. While lifestyle intervention is a primary treatment, the molecular mechanisms driving the regression of advanced fibrosis remain poorly understood. We report a man in his 30 s with severe obesity (BMI 35.2 kg/m[2]) and advanced fibrosis (liver stiffness measurement [LSM] 18 kPa) who underwent a 12-month caloric restriction and resistance training program. He achieved 33.8% weight loss while preserving skeletal muscle, resulting in normalized liver enzymes and an 80.6% reduction in LSM. Comparative serum proteomic analysis revealed that the "Neutrophil extracellular traps (NETs) formation" pathway was the most significantly upregulated, contrasting with downregulated metabolic pathways. Detailed mapping confirmed increased expression of NETosis-essential proteins, including peptidylarginine deiminase 4 (PAD4), neutrophil elastase (NE), myeloperoxidase (MPO), and citrullinated histone H3 (citH3), alongside upstream signaling such as ROS, Akt/mTOR, and NADPH oxidase components. This case demonstrates that intensive lifestyle intervention can induce rapid regression of advanced fibrosis in MASLD. The transition from metabolic stress to NETosis activation indicates that neutrophil-mediated immune regulation may be a key driver in the systemic and hepatic remodeling process.

A novel rotary variable stiffness actuator (VSA) is presented to meet the requirements of the variable stiffness drive for a robot joint. Considering the characteristics of a rotary magnetorheological damper (MRD) that has controllable torque and fast response, a servo motor and a rotary MRD are combined to form a VSA. The principle of variable stiffness drive is analyzed according to the frame of the VSA. The rotary MRD for the VSA is designed, and the electromagnetic field distribution in the damper is analyzed with the finite element method. Then, the torque and magnetomotive force value of the damper are calculated. Based on the configuration of the VSA and the mechanical characteristics of the damper, the variable stiffness control method is proposed. Based on these factors, the rotary MRD and the VSA are developed, and the performance tests are worked out. The experimental results show that the test results of the damper torque are close to the calculation results, and different stiffness coefficients can be set in the control program of the VSA. The test results of the stiffness coefficients are close to the set values. Moreover, the approach proposed in this article provides valuable insights into the utilization of rotary MRD for the development of variable stiffness robotic systems.

Physiological palpation serves as a primary clinical modality for identifying pathological changes in tissue compliance. However, its diagnostic precision is inherently limited by the subjective nature of human haptic perception and the lack of quantifiable mechanical metrics. This work describes a bio-inspired, portable tactile interface engineered for the non-invasive and real-time characterization of tissue stiffness. The system incorporates multimodal piezoresistive sensing elements that emulate the specific mechanotransduction functions of cutaneous receptors, namely Merkel disks and Ruffini endings. By integrating Hertzian contact mechanics to decouple pressure and strain signals, the platform analytically derives the effective Young's modulus of heterogeneous soft tissues. The developed sensor architecture exhibits a functional range of 0-600 kPa and a gauge factor of 10.8, facilitating high-fidelity detection of subcutaneous anomalies. Validation against various nodule geometries and depths demonstrates that the system achieves a diagnostic resolution surpassing conventional manual assessments. Furthermore, the integration of wireless data processing enables instantaneous, on-site mechanical profiling. This platform provides a scalable framework for objective diagnostics, robotic haptics, and continuous physiological monitoring, establishing a robust bridge between qualitative clinical observation and quantitative biomechanical analysis.