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Natural cartilage exhibits superior lubricity as well as an ultra‐long service lifetime, which is related to its surface hydration, load‐bearing, and deformation recovery feature. Until now, it is of great challenge to develop reliable cartilage lubricating materials or coatings with persistent robustness. Inspired by the unique biochemical structure and mechanics of natural cartilage, the study reports a novel cartilage‐hydrogel composed of top composite lubrication layer and bottom mechanical load‐bearing layer, by covalently manufacturing thick polyelectrolyte brush phase through sub‐surface of tough hydrogel matrix with multi‐level crystallization phase. Due to multiple network dissipation mechanisms of matrix, this hydrogel can achieve a high compression modulus of 11.8 MPa, a reversible creep recovery (creep strain: ≈2%), along with excellent anti‐swelling feature in physiological medium (v/v0 < 5%). Using low‐viscosity PBS as lubricant, this hydrogel demonstrates persistent lubricity (average COF: ≈0.027) under a high contact pressure of 2.06 MPa with encountering 100k reciprocating sliding cycles, negligible wear and a deformation recovery of collapse pit in testing area. The extraordinary lubrication performance of this hydrogel is comparable to but beyond the natural animal cartilage, and can be used as compliant coating for implantable articular material of UHMWPE to present, offering more robust lubricity than current commercial system. [ABSTRACT FROM AUTHOR]

The simultaneous achievement ‐under physiologically high contact pressures‐ of ultra‐low friction, nearly zero surface wear, and long lifetime in the development of human cartilage prosthetics is still a big challenge. In this work, inspired by the unique lubrication mechanism of scallion leaves resulting from the synergy of oriented surface micro‐topography and mucus hydration, a novel layered soft hydrogel as cartilage prototype is developed by chemically embedding thick hydrophilic polyelectrolyte brush chains into the sub‐surface of a high strength anisotropic hydrogel bulk. It exhibits an anisotropic polymer network with unique mechanical properties (tensile strength: 8.3 to 23.7 MPa; elastic modulus 20.0 to 30.0 MPa), anisotropic hydrated surface texture, super‐lubricity, and excellent wear resistance. Thydrogel architecture can exhibit low coefficient of friction (COF) less than ≈0.01 under a wide range of contact stresses (0.2 to 2.4 MPa) and maintain cartilage‐like long‐lasting (50k sliding cycles) robust super‐lubricity (COF ≈ 0.006) and nearly‐zero wear under high contact pressure (≈2.4 MPa) condition. Theoretical underpinning reveals how multiscale surface anisotropy, mechanics, and hydration regulate super‐low friction generation. This work provides a novel design paradigm for the fabrication of robust soft materials with extraordinary lubricity as implantable prototypes and coatings. [ABSTRACT FROM AUTHOR]

Growing lubricating hydrogel coatings in controllable manners on diverse material surfaces demonstrates promising applications. Here, a surface modification method is reported for in situ growing hydrogel coatings onto surfaces of diverse substrates in the absence of UV assistance. It is performed by decorating substrates with a universal mussel‐inspired synthetic adhesive with catechol groups. Upon being immersed in reaction solution, these groups can assist substrate bonding and in situ capture and reduce Fe3+ into Fe2+ for decomposing S2O82− into SO4−⋅ catalytically at the interface to initiate interface polymerization of monomers. As a result, hydrogel coatings with controllable thickness could be grown on surfaces of arbitrary substrates to change their surface characteristics regardless of materials size, category, geometry and transparency, implying considerable potential in surface engineering. [ABSTRACT FROM AUTHOR]

Hydrogels have been considered as potential candidates for cartilage replacement due to their high‐water content, extreme network hydration, excellent biocompatibility and tunable mechanical properties. Currently, the development of high‐performance cartilage‐inspired hydrogel lubrication materials has become a hot topic in the field of biomedical materials. This review focusses on the recent development of cartilage‐inspired high‐strength hydrogels from the viewpoints of bionic surface/interface and biotribology. Specifically, the composition structure and extraordinary lubrication mechanism of the natural articular cartilage are overviewed first. Subsequently, some of the novel biomimetic design strategies for preparing high strength cartilage hydrogels with various network structures are summarised in detail, while systematic evaluation of lubrication properties and mechanisms are discussed. Furthermore, new surface modification means for improving the lubrication feature of high strength cartilage hydrogel materials are presented. In addition, in order to demonstrate the application potential of cartilage hydrogels in clinical, several bonding methods to decorate hydrogels onto surfaces of natural bone tissues or artificial joint materials are introduced. Finally, current challenges and future research directions are discussed for cartilage‐inspired hydrogel lubrication materials. [ABSTRACT FROM AUTHOR]

Delayed wound healing has a profound impact on patients, healthcare, and society. Platelet‐rich plasma (PRP) gel, as a preparation for regenerative medicine, has proven to be of clinical value in various wound treatments. Nevertheless, its weak mechanical properties and consequent burst release effect have restricted its application and efficacy. Here, an engineered PRP dual‐network hydrogel (named DN gel) based on sodium alginate is constructed through a simple "one‐step" activation process. Its improved gelling property and sustained release of growth factors may be beneficial for clinical use. Evaluations in rats indicate that DN gel promote wound healing in terms of rapid re‐epithelialization, up‐regulated growth factor levels and early transitions in the wound healing and angiogenesis stages. As a proof of concept, DN gel also exhibits superior healing efficiency in a porcine wound model. These results demonstrate the great potential of transforming this hydrogel into the next generation of PRP‐based bioactive wound dressing. [ABSTRACT FROM AUTHOR]

Consumer confidence and trust, as it relates to the food system, is one of the most sensitive areas within consumers' understanding of food. Surveys have shown that a large majority of people would like to learn more about agriculture and food manufacturing, with young people being among those most eager for more information about where their food comes from. Food‐focused educational resources often go unused due to teachers' lack of familiarity with the subject area, the pressures of standardized testing, and lack of alignment to state content standards. Building on the success of the Hands On Classrooms platform that developed and validated curricula with high adoption rates by teachers and a demonstrated impact on student knowledge and self‐efficacy, a new curriculum on food system and food processing was developed and pilot tested. Two teachers from rural Virginia and Tennessee participated in the study. Both teachers received online professional development prior to implementation. Students were given pretests and posttests to measure (a) what impact does the curriculum have on students' knowledge of food systems and processing and (b) to what extent does the curriculum have an impact on student's self‐reported skills related to these topics? A total of 87 students completed the assessments and showed significant improvements from pretest to posttest on both knowledge (p <.001) and skills (p <.001) related specifically to where food comes from and how it is processed, content that is typically not covered in middle school curriculum. Further research can be undertaken to measure the impact on others in different geographic and socioeconomic areas to provide additional data to validate the program. [ABSTRACT FROM AUTHOR]

Porous hydrogels with high porosity can achieve high matter diffusion and transport efficiency. Achieving both ultrahigh porosity and excellent mechanical properties in porous hydrogels remains a long‐standing challenge, considerably hindering their use in high load‐bearing elastic scaffolds such as artificial articular cartilages and meniscus replacements. Herein, a novel crystalline‐constrained multi‐solvents template preparation method is proposed for synthesizing highly porous hierarchical polyvinyl alcohol hydrogels (P‐exogel) with excellent mechanical properties. The enhanced mechanical characteristics of the P‐exogel are attributed to the crystallinity‐induced network anti‐swelling effect of the pore walls during dynamic template removal. The P‐exogel exhibits a hierarchical and interconnected pore structure with high porosity (81.69%), resulting in ultrafast surface wetting with water (in less than 10 ms). Moreover, the P‐exogel exhibits good tensile breaking strength (2.47 ± 0.53 MPa) with elongation of more than 400%, high toughness (5.61 ± 1.65 MJ m−3), and excellent elastic recovery performance. The pre‐crack testing results further confirm the ultrahigh fracture resistance (18.73 ± 2.52 KJ m−2) of the P‐exogel, which almost surpasses those of all reported and commercial porous hydrogels. The unique network microstructure of the P‐exogel ensures its highly efficient and reversible liquid absorption and release ability during dynamic loading–unloading processes, confirming its great application potential in high load‐bearing elastic scaffolds. [ABSTRACT FROM AUTHOR]