Nitric oxide (NO) is a highly potent radical with a wide spectrum of physiological activities. Depending on the concentration, it can enhance endothelial cell proliferation in a growth factor‐free medium, mediate angiogenesis, accelerate wound healing, but may also lead to tumor progression or induce inflammation. Due to its multifaceted role, NO must be administered at a right dose and at the specific site. Many efforts have focused on developing NO‐releasing biomaterials; however, NO short half‐life in human tissues only allows this molecule to diffuse over short distances, and significant challenges remain before the full potential of NO can be realized. Here, an overview of platforms that are engineered to release NO via catalytic or noncatalytic approaches is presented, with a specific emphasis on progress reported in the past five years. A number of NO donors, natural enzymes, and enzyme mimics are highlighted, and recent promising developments of NO‐releasing scaffolds, particles, and films are presented. In particular, key parameters of NO delivery are discussed: 1) NO payload, 2) maximum NO flux, 3) NO release half‐life, 4) time required to reach maximum flux, and 5) duration of NO release. Advantages and drawbacks are reviewed, and possible further developments are suggested.

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Dry reforming of methane (DRM) is a promising chemical approach to convert greenhouse gases CO2 and CH4 into valuable fuels. Previous experimental study has shown that the addition of alkaline earth can promote the activity and stability of the Ni-based catalyst. However, the physical structure of alkaline earth additives on supports and their interaction with Ni particles should have significant influence for the catalytic performance of catalysts. To clarify the synthesis–structure–activity relationship for further improving these catalysts, the underlying reaction mechanism for DRM over size-confined Ni–CaO catalysts on neutral supports and the structure/effect of CaO as promoter were investigated combining density functional theory (DFT) calculation and experimental studies. The favored active sites for all elementary reactions were identified, and the activation energies of the reactions were calculated for the determination of the primary reaction pathways. DFT results found a cooperation effect between Ni and CaO, where the interface dissociates CO2, Ni activates CH4 dehydrogenation, and CaO attracts CO2. The interface between Ni and CaO was found to provide another channel to activate CO2 and decrease the energy barrier of CHO formation, contributing to the high efficiency and long-term stability of the catalyst. On the basis of the DFT results, the optimum stacking order between Ni and CaO was proposed, in good agreement with the experimental studies that synthesized and compared four catalysts with different Ni–CaO structures. The proposed Ni–CaO composite catalyst should be a promising catalyst for potential application in industrial dry reforming processes.

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The highly diverse biological roles of nitric oxide (NO) in both physiological and pathophysiological processes have prompted great interest in the use of NO as a therapeutic agent in various biomedical applications. NO can exert either protective or deleterious effects depending on its concentration and the location where it is delivered or generated. This double-edged attribute, together with the short half-life of NO in biological systems, poses a major challenge to the realization of the full therapeutic potential of this molecule. Controlled release strategies show an admirable degree of precision with regards to the spatiotemporal dosing of NO but are disadvantaged by the finite NO deliverable payload. In turn, enzyme-prodrug therapy techniques afford enhanced deliverable payload but are troubled by the inherent low stability of natural enzymes, as well as the requirement to control pharmacokinetics for the exogenous prodrugs. The past decade has seen the advent of a new paradigm in controlled delivery of NO, namely localized bioconversion of the endogenous prodrugs of NO, specifically by enzyme mimics. These early developments are presented, successes of this strategy are highlighted, and possible future work on this avenue of research is critically discussed.

Farmed mink (Neovison vison) is one of the most important fur-bearing species worldwide, and coat colour is a crucial qualitative characteristic that contributes to the economic value of the fur. To identify additional genes that may play important roles in coat colour regulation, Illumina/Solexa high-throughput sequencing technology was used to catalogue the global gene expression profiles in mink skin with two different coat colours (black and white). RNA-seq analysis indicated that a total of 12,557 genes were differentially expressed in black versus white minks, with 3,530 genes up-regulated and 9,027 genes down-regulated in black minks. Significant differences were not observed in the expression of MC1R and TYR between the two different coat colours, and the expression of ASIP was not detected in the mink skin of either coat colour. The expression levels of KITLG, LEF1, DCT, TYRP1, PMEL, Myo5a, Rab27a and SLC7A11 were validated by qRT-PCR, and the results were consistent with RNA-seq analysis. This study provides several candidate genes that may be associated with the development of two coat colours in mink skin. These results will expand our understanding of the complex molecular mechanisms underlying skin physiology and melanogenesis in mink and will provide a foundation for future studies.