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Having been predominantly observed in rigid metal and metal alloys since 1865, the magnetoelastic effect was recently experimentally discovered in a soft matter system and used as a new working mechanism for energy and health care applications. Here, a theoretical framework is presented and proven to be universally accurate and robust in interpreting the giant magnetoelastic effect across soft systems subjected to various deformation modes, micromagnet concentrations, magnetization profiles, and geometric structures. The theory uncovers substantial, unique magnetoelastic phenomena in soft systems, including the magnetic pole reversal under localized compression. This work lays a firm foundation for an in-depth understanding and practical applications of the giant magnetoelastic effect in soft matter systems. 

Abstract This study investigates the vertical structure and related dynamical and energy conversion processes that aided the development of two east Pacific easterly waves (EWs) during the 2019 OTREC (Organization of Tropical East Pacific Convection) campaign period. The initial mesoscale convective systems (MCSs) that seeded both disturbances formed near the Panama Bight and developed into EWs near the Papagayo jet exit region. In the MCS stage, both disturbances were characterized by top‐heavy vertical motions and midlevel vorticity near the maximum vorticity center. The deep convection caused strong latent heating and eddy available potential energy (EAPE) generation and conversion to eddy kinetic energy (EKE) in the upper levels. When the disturbances moved to the south of the Papagayo jet, they interacted with the low‐level shear vorticity there, enhancing low‐level stretching and vorticity. Subsequently, the top‐heavy upward motion intensified and led to enhanced stretching and vorticity intensification at midlevels. The enhanced stretching on the southwest side also favored the formation of southwest‐northeast tilted vorticity at midlevels that characterizes EWs. After the EWs formed near the jet exit, the vertical motion weakened and became more bottom‐heavy, with the maximum vorticity shifting to lower levels. This change in the vertical motion profile near the jet exit region is likely modulated by the lower sea surface temperature, reduced moisture, and weaker convective instability. While EAPE‐to‐EKE conversion weakened during this period, the low‐level barotropic conversion of EKE in the jet exit served as the primary energy source for the EWs. 

Abstract The severe mismatch between solid bioelectronics and dynamic biological tissues has posed enduring challenges in the biomonitoring community. Here, we developed a reconfigurable liquid cardiac sensor capable of adapting to dynamic biological tissues, facilitating ambulatory cardiac monitoring unhindered by motion artifacts or interference from other biological activities. We employed an ultrahigh-resolution 3D scanning technique to capture tomographic images of the skin on the wrist. Then, we established a theoretical model to gain a deep understanding of the intricate interaction between our reconfigurable sensor and dynamic biological tissues. To properly elucidate the advantages of this sensor, we conducted cardiac monitoring alongside benchmarks such as the electrocardiogram. The liquid cardiac sensor was demonstrated to produce stable signals of high quality (23.1 dB) in ambulatory settings. 

Abstract Stretchable supercapacitors (SCs) have attracted significant attention in developing power‐independent stretchable electronic systems due to their intrinsic energy storage function and unique mechanical properties. Most current SCs are generally limited by their low stretchability, complicated fabrication process, and insufficient performance and robustness. This study presents a facile method to fabricate arbitrary‐shaped stretchable electrodes via 4D printing of conductive composite from reduced graphene oxide, carbon nanotube, and poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate. The electrode patterns of an arbitrary shape can be deposited onto prestretched substrates by aerosol‐jet printing, then self‐organized origami (ridge) patterns are generated after releasing the substrates from holding stretchers due to the mismatched strains. The stretchable electrodes demonstrate superior mechanical robustness and stretchability without sacrificing its outstanding electrochemical performance. The symmetric SC prototype possesses a gravimetric capacitance of ≈21.7 F g⁻¹at a current density of 0.5 A g⁻¹and a capacitance retention of ≈85.8% from 0.5 to 5 A g⁻¹. A SC array with arbitrary‐shaped electrodes is also fabricated and connected in series to power light‐emitting diode patterns for large‐scale applications. The proposed method paves avenues for scalable manufacturing of future energy‐storage devices with controlled extensibility and high electrochemical performance.