Ultra-Highly Stiff and Tough Shape Memory Polyurea with Unprecedented Energy Density by Precise Slight Cross-Linking.

Shape memory polymers (SMPs) have attracted significant attention and hold vast potential for diverse applications. Nevertheless, conventional SMPs suffer from notable shortcomings in terms of mechanical properties, environmental stability, and energy density, significantly constraining their practical utility. Here, inspired by the structure of muscle fibers, an innovative approach that involves the precise incorporation of subtle, permanent cross-linking within a hierarchical hydrogen bonding supramolecular network is reported. This novel strategy has culminated in the development of covalent and supramolecular shape memory polyurea, which exhibits exceptional mechanical properties, including high stiffness (1347 MPa), strength (82.4 MPa), and toughness (312.7 MJ m-3), ensuring its suitability for a wide range of applications. Furthermore, it boasts remarkable recyclability and repairability, along with excellent resistance to moisture, heat, and solvents. Moreover, the polymer demonstrates outstanding shape memory effects characterized by a high energy density (24.5 MJ m-3), facilitated by the formation of strain-induced oriented nanostructures that can store substantial amounts of entropic energy. Simultaneously, it maintains a remarkable 96% shape fixity and 99% shape recovery. This delicate interplay of covalent and supramolecular bonds opens up a promising pathway to the creation of high-performance SMPs, expanding their applicability across various domains.

Computer gaming alters resting-state brain networks, enhancing cognitive and fluid intelligence in players: evidence from brain imaging-derived phenotypes-wide Mendelian randomization.

The debate on whether computer gaming enhances players' cognitive function is an ongoing and contentious issue. Aiming to delve into the potential impacts of computer gaming on the players' cognitive function, we embarked on a brain imaging-derived phenotypes (IDPs)-wide Mendelian randomization (MR) study, utilizing publicly available data from a European population. Our findings indicate that computer gaming has a positive impact on fluid intelligence (odds ratio [OR] = 6.264, P = 4.361 × 10-10, 95% confidence interval [CI] 3.520-11.147) and cognitive function (OR = 3.322, P = 0.002, 95% CI 1.563-7.062). Out of the 3062 brain IDPs analyzed, only one phenotype, IDP NET100 0378, was significantly influenced by computer gaming (OR = 4.697, P = 1.10 × 10-5, 95% CI 2.357-9.361). Further MR analysis suggested that alterations in the IDP NET100 0378 caused by computer gaming may be a potential factor affecting fluid intelligence (OR = 1.076, P = 0.041, 95% CI 1.003-1.153). Our MR study lends support to the notion that computer gaming can facilitate the development of players' fluid intelligence by enhancing the connectivity between the motor cortex in the resting-state brain and key regions such as the left dorsolateral prefrontal cortex and the language center.