The regeneration of artificial bone substitutes is a potential strategy for repairing bone defects. However, the development of substitutes with appropriate osteoinductivity and physiochemical properties, such as water uptake and retention, mechanical properties, and biodegradation, remains challenging. Therefore, there is a motivation to develop new synthetic grafts that possess good biocompatibility, physiochemical properties, and osteoinductivity. Here, we fabricate a biocompatible scaffold through the covalent crosslinking of graphene oxide (GO) and carboxymethyl chitosan (CMC). The resulting GO‐CMC scaffold shows significant high water retention (44% water loss) compared with unmodified CMC scaffolds (120% water loss) due to a steric hindrance effect. The modulus and hardness of the GO‐CMC scaffold are 2.75‐ and 3.51‐fold higher, respectively, than those of the CMC scaffold. Furthermore, the osteoinductivity of the GO‐CMC scaffold is enhanced due to the π–π stacking interactions of the GO sheets, which result in striking upregulation of osteogenesis‐related genes, including osteopontin, bone sialoprotein, osterix, osteocalcin, and alkaline phosphatase. Finally, the GO‐CMC scaffold exhibits excellent reparative effects in repairing rat calvarial defects via the synergistic effects of GO and bone morphogenetic protein‐2. This study provides new insights for developing bone substitutes for tissue engineering and regenerative medicine.

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Senescence is a key factor resulting in deterioration of non-climacteric fruit. NAC transcription factors are important regulators in plant development and abiotic stress responses, yet little information regarding the role of NACs in regulating non-climacteric fruit senescence is available. In this study, we cloned 13 NAC genes from litchi (Litchi chinensis) fruit, and analyzed subcellular localization and expression profiles of these genes during post-harvest natural and low-temperature-delayed senescence. Of the 13 NAC genes, expression of LcNAC1 was up-regulated in the pericarp and pulp as senescence progressed, and was significantly higher in senescence-delayed fruit than that in naturally senescent fruit. LcNAC1 was induced by exogenous ABA and hydrogen peroxide. Yeast one-hybrid analysis and transient dual-luciferase reporter assay showed that LcNAC1 was positively regulated by the LcMYC2 transcription factor. LcNAC1 activated the expression of LcAOX1a, a gene associated with reactive oxygen species regulation and energy metabolism, whereas LcWRKY1 repressed LcAOX1a expression. In addition, LcNAC1 interacted with LcWRKY1 in vitro and in vivo. These results indicated that LcNAC1 and LcWRKY1 form a complex to regulate the expression of LcAOX1a antagonistically. Taken together, the results reveal a hierarchical and co-ordinated regulatory network in senescence of harvested litchi fruit.

We report α‐MoO3 flowers as a highly effective organics adsorbent for the first time. With α‐MoO3 microfibers (MFs), α‐MoO3 flowers uniformly self‐assemble on a carbon cloth, serving as a great organics scavenger. They not only provide a high specific surface area but also possess van der Waals force, both of which guarantee a high adsorption efficiency for multiple organics. Nearly 100% of Rhodamine B (RhB), methylene blue (MB), and crystal violet (CV) are rapidly adsorbed while flowing through the designed α‐MoO3 flower‐based filtration device. Even after five recycling times, its high adsorption efficiency toward RhB remains unaffected. The adsorption capacity of α‐MoO3 flowers for RhB, MB, and CV reaches up to 4974, 6217, and 3886 mg/m2, respectively. Additionally, this novel adsorbent can adapt to a wide pH range, maintaining the excellent capacity of 4774 and 4473 mg/m2 toward RhB at pH of 2.0 and 12.0. The α‐MoO3 flowers can also adsorb other organics, including MO, noroxin, and tetracycline hydrochloride. Moreover, the free‐standing α‐MoO3 flowers on a carbon cloth realize the adsorptive filtration for organics removal, which not only require no conditions and no energy consumption but also avoid secondary pollution to the water as compared to the powdery adsorbents.

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A porous hybrid, namely PW12@TiO2–Si(Et)Si/Pba, is fabricated by the modification of PW12@TiO2–Si(Et)Si with pyridine boronic acid and used for glycoprotein depletion.

Removal of heavy metals from food material by growing micro-organisms is limited by the toxicity to cells. In this study, different preincubation treatments were investigated to analyze their effects on cadmium resistance and removal ability of Pichia kudriavzevii A16 and Saccharomyces cerevisiae CICC1211. Sucrose preincubation improved the cadmium resistance of both yeast cells and increased the cadmium-removal rate of P. kudriavzevii A16. An evident decrease of intracellular and cell-surface cadmium accumulation was observed after sucrose preincubation, which may be the primary reason responsible for the improved cadmium resistance. Flow cytometry assay showed that sucrose significantly reduced the production of reactive oxygen species (ROS) and cell death rate of both yeasts under cadmium compared with those normally cultured cells. Under cadmium stress, the content of both protein carbonyls and malonyldialdehyde were also reduced by the addition of sucrose, the results were in accordance with the tendency of ROS, exhibiting a defending function of sucrose. Osmotic regulators as proline and trehalose were increased by sucrose preincubation in P. kudriavzevii A16 in the presence of cadmium. The results suggested that sucrose preincubation could be applied to improve cadmium resistance and removal rate of yeasts. K E Y W O R D Scadmium removal, cadmium resistance, cross-protection, Pichia kudriavzevii, sucrose preincubation