Osteochondral (OC) defects pose an enormous challenge with no entirely satisfactory repair strategy to date. Herein, a 3D printed gradient hydrogel scaffold with a similar structure to that of OC tissue is designed, involving a pure hydrogel‐based top cartilage layer, an intermediate layer for calcified cartilage with 40% (w w−1) nanohydroxyapatite (nHA) and 60% (w w−1) hydrogel, and a 70/30% (w w−1) nHA/hydrogel‐based bottom subchondral bone layer. This study is conducted to evaluate the efficacy of the scaffold with nHA gradients in terms of its ability to promote OC defect repair. The fabricated composites are evaluated for physicochemical, mechanical, and biological properties, and then implanted into the OC defects in 56 rats. Overall, bone marrow stromal cells (BMSCs)‐loaded gradient scaffolds exhibit superior repair results as compared to other scaffolds based on gross examination, micro‐computed tomography (micro‐CT), as well as histologic and immunohistochemical analyses, confirming the ability of this novel OC graft to facilitate simultaneous regeneration of cartilage‐subchondral bone.

The relationship between species richness and evenness across communities remains an unsettled issue in ecology from both theoretical and empirical perspectives. As a result, we do not know the mechanisms that could generate a relationship between species richness and evenness, and how this responds to spatial scale. Here we examine the relationship between species richness(S) and evenness (Pielou’s J′ evenness) using a chronosequence of successional sub-alpine meadow communities in the eastern Qinghai-Tibetan Plateau. These meadows range from natural community (never farmed), to those that have been protected from agricultural exploitation for periods ranging from 1 to 10 years. A total of 30 sampling quadrats with size of 0.5 m×0.5 m were laid out along two transects at each meadow. Using correlation analyses we found a consistent negative correlation between S and J′ in these communities along the successional gradient at the sampling scale of 0.5 m×0.5 m. We also explored the relationship between S and J′ at different sampling scales (from 0.5 m×0.5 m to10 m×10 m) using properly measured ramet-mapped data of a10 m×10 m quadrat in the natural community. We found that S was negatively corrected with J′ at the scales of 0.5 m×0.5 m to 2 m×2 m, but such a relationships disappeared at relative larger scales (≥2 m×4 m). When fitting different species abundance models combined with trait-specific methods, we found that niche preemption may be the determining mechanism of species evenness along the succession gradient. Considering all results together, we can conclude that such niche differentiation and spatial scale effects may help to explain the maintenance of high species richness in sub-alpine meadow communities.

MicroRNAs (miRNAs) are small, noncoding RNAs that play an important role in many key biological processes, including development, cell differentiation, the cell cycle and apoptosis, as central post-transcriptional regulators of gene expression. Recent studies have shown that miRNAs can act as oncogenes and tumor suppressors depending on the context. The present work focuses on the physiological significance of miRNAs and their role in regulating the switching behavior. We illustrate an abstract model of the Myc/E2F/miR-17-92 network presented by Aguda et al. (2008), which is composed of coupling between the E2F/Myc positive feedback loops and the E2F/Myc/miR-17-92 negative feedback loop. By systematically analyzing the network in close association with plausible experimental parameters, we show that, in the presence of miRNAs, the system bistability emerges from the system, with a bistable switch and a one-way switch presented by Aguda et al. instead of a single one-way switch. Moreover, the miRNAs can optimize the switching process. The model produces a diverse array of response-signal behaviors in response to various potential regulating scenarios. The model predicts that this transition exists, one from cell death or the cancerous phenotype directly to cell quiescence, due to the existence of miRNAs. It was also found that the network involving miR-17-92 exhibits high noise sensitivity due to a positive feedback loop and also maintains resistance to noise from a negative feedback loop.

The probabilistic linguistic term sets (PLTSs) allow experts to express their preferences regarding one linguistic term over another. Nowadays, multicriteria decision‐making methods for PLTSs are very popular, and Bai et al’s multicriteria decision‐making method based on the possibility degree formula for PLTSs cannot be ranked in some situations. In this paper, we first propose a new possibility degree method for PLTSs and state their properties, and we use this new possibility degree method to solve the drawbacks of Bai et al’s possibility degree method. Second, we propose a probabilistic linguistic weight average (PLWA) and probabilistic linguistic order weight average (PLOWA) operator and state their properties. Then, based on the new possibility degree method and the PLWA (PLOWA) operator, we propose a multicriteria decision‐making method based the PLWA (PLOWA) operator. Finally, we utilize an example to illustrate the interrelationships between our method and Bai et al’s method. The result shows that our multicriteria decision‐making method is more rational.