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Excessive ultraviolet (UV) exposure can lead to sunburn, characterized by skin barrier damage, inflammation, pain, and an increased risk of skin cancer. Recombinant collagens have gradually attracted attention due to their high purity, low immunogenicity, batch-to-batch consistency, and excellent solubility. Additionally, the type of dressing significantly affects wound repair. Gels are ideal for sunburn treatment because they maintain a moist environment, adhere firmly, and do not need to be removed. Herein, we have created bioactive triple-helical recombinant collagen (THRC) gels for improved healing of sunburned skin. The THRC gels remained stable after a three-month stability test, displaying a rheological behavior characteristic of non-Newtonian pseudoplastic fluids. In vivo skin irritation tests conducted on New Zealand rabbits demonstrated that THRC gels were safe for use. A sunburned mice model was established to study the biological effects of THRC gels. Non-invasive combo evaluations indicated that THRC gels exhibited an exceptional capability of recovering dermis density, erythema index (EI), hydration, and transepidermal water loss (TEWL) of sunburned skin to a healthy state. Histological observations revealed that THRC gels significantly enhanced the repair of damaged skin by accelerating the recovery process, promoting collagen deposition and regeneration. Molecular biological characterizations further demonstrated their remarkable antioxidant properties, including the inhibition of lipoperoxidation and the enhancement in superoxide dismutase (SOD) and glutathione (GSH) activities. These safe and bioactive recombinant collagen gels provide a novel approach for sunburn repair and show potential for long-term cosmetic benefits. [ABSTRACT FROM AUTHOR]

Ethnic tourism is being advocated in China to assist regional development and poverty alleviation. However, the arrival of tourism developers who are largely external to local communities has led to changes in economic and governance arrangements at the local level. To understand how local communities are impacted and how they respond to and potentially recover from these changes, we examined Miao (Hmong) villages in Hunan Province, China. We consider how Chinese ethnic communities can simultaneously be vulnerable and yet still display resilience when they are exposed to tourism-induced structural changes that disempower them. We found that ethnic tourism created opportunities for knowledge sharing, which facilitated family businesses and skill enhancement. However, lack of local capital created dependence on external developers, and tourism increased the vulnerability of ethnic communities. Nevertheless, local people developed coping strategies to address the long-term economic and governance changes induced by tourism, despite also experiencing increasing disempowerment and vulnerability. We show that, even with top-down tourism governance models that are typically associated with the marginalization of local communities, everyday economic life was characterized by hybridity – simultaneous resilience and susceptibility, empowerment and disempowerment, and self-organization and dependency. [ABSTRACT FROM AUTHOR]

The viscoelasticity of mechanically sensitive tissues such as periodontal ligaments (PDLs) is key in maintaining mechanical homeostasis. Unfortunately, PDLs easily lose viscoelasticity (e.g., stress relaxation) during periodontitis or dental trauma, which disrupt cell–extracellular matrix (ECM) interactions and accelerates tissue damage. Here, Pluronic F127 diacrylate (F127DA) hydrogels with PDL‐matched stress relaxation rates and high elastic moduli are developed. The hydrogel viscoelasticity is modulated without chemical cross‐linking by controlling precursor concentrations. Under cytomechanical loading, F127DA hydrogels with fast relaxation rates significantly improved the fibrogenic differentiation potential of PDL stem cells (PDLSCs), while cells cultured on F127DA hydrogels with various stress relaxation rates exhibited similar fibrogenic differentiation potentials with limited cell spreading and traction forces under static conditions. Mechanically, faster‐relaxing F127DA hydrogels leveraged cytomechanical loading to activate PDLSC mechanotransduction by upregulating integrin–focal adhesion kinase pathway and thus cytoskeletal rearrangement, reinforcing cell–ECM interactions. In vivo experiments confirm that faster‐relaxing F127DA hydrogels significantly promoted PDL repair and reduced abnormal healing (e.g., root resorption and ankyloses) in delayed replantation of avulsed teeth. This study firstly investigated how matrix nonlinear viscoelasticity influences the fibrogenesis of PDLSCs under mechanical stimuli, and it reveals the underlying mechanobiology, which suggests novel strategies for PDL regeneration. [ABSTRACT FROM AUTHOR]