Herein, a new type of injectable carboxymethyl chitosan (CMCh) hydrogel wound dressing with self-healing properties is constructed. First, CMCh samples are homogeneously synthesized in alkali/urea aqueous solutions. Subsequently, trivalent metal ions of Fe3+ and Al3+ are introduced to form coordination bonds with CMCh, leading to an ultrafast gelation process. A series of hydrogels can be obtained by altering the concentration of CMCh and the relative content of metal ions. Owing to the dynamic and reversible characteristics of the coordination bonds, the hydrogel exhibits self-healing, self-adaption, and thermoresponsive ability. Moreover, due to the interaction between the amino groups on CMCh and SO4 2–, the hydrogel undergoes phase separation and can be painlessly detached from the skin with little residue. Taking advantage of all these characteristics, the hydrogel is used as a wound dressing and can significantly accelerate skin tissue regeneration and wound closure. This hydrogel has great potential in the application of tissue engineering.

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Wound healing is a clinical challenge, and nontoxic, nonadherent wound dressings that promote healing are urgently needed. Herein, hydroxybutyl chitosans (HBCSs) with the degree of substitution (DS) from 0.41 to 1.38 were synthesized in alkali/urea aqueous solutions, from which sponge-like dressings were prepared by freeze-drying. The pore size of the sponges was in the range of 14.8–18.4 μm, and the porosity was about 98–99%. The compressive strength of the sponges decreased with increasing DS of HBCS. Cytocompatibility studies with normal human dermal fibroblast (NHDF) cells demonstrated that HBCSs were nontoxic and could even promote the growth of fibroblasts. Further tests revealed that HBCS-3 (DS = 0.85) and HBCS-5 (DS = 1.38) exhibited better hemocompatibility and a low blood-clotting index (BCI). Therefore, these two samples were selected as model dressings for in vivo wound-healing assessment in rats. The experiments suggested that HBCS-3 significantly shortened the wound recovery period compared with HBCS-5, chitosan, and gauze by facilitating epithelialization, collagen deposition, and neovascularization and activating the immune system. The results highlighted the potential of HBCSs as efficient dressings for promoting wound healing.

This paper reports the results of a survey on Chinese researchers' perceptions and use of open access journals (OAJs). A total of 381 Chinese researchers from different universities and disciplines were investigated through an online questionnaire survey in August and September 2018. The results showed that most Chinese researchers are familiar with and have positive attitude to OAJs. They know OAJs mainly through their peers, colleagues, and friends. PubMed Central, PLoS, and COAJ (China Open Access Journals) are the most well-known OAJ websites among Chinese researchers. As for use, most of the respondents read and cite OAJs frequently and have experience of publishing in OAJs. However, they strongly prefer to use OAJs indexed in reputable databases (e.g. Web of Science, WoS) when making publishing decisions. Significant differences can be seen among disciplines, with researchers in HSS areas using OAJs less frequently than researchers from other disciplines, although they have the same positive attitudes and are equally well informed about them. Younger researchers preferred to rely on prestigious institutions and authors when using OAJs.

Self-healing and easy-to-shape mineralized hydrogels for iontronics were fabricated through physically cross-linked PVP and CaCO3.