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In this paper, zirconium-based MOF (Zr-MOFs) materials, namely UIO-66, UIO-66-NH2, GMA-UIO-66 and NB-UIO-66, were selected as fillers to enhance the mechanical properties of polydicyclopentadiene (PDCPD) nanocomposites, and Zr-MOFs/PDCPD nanocomposites were prepared by in situ polymerization. The functional groups and morphology of Zr-MOFs were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and field emission scanning electron microscopy (SEM). The mechanical properties of Zr-MOFs/PDCPD composites were studied by tensile toughness, notched impact strength and bending strength test. Furthermore, the optimum Zr-MOFs loading was determined. The results show that when the mass fraction of NB-UIO-66 is 0.4%, the composites' tensile toughness, flexural strength, impact strength and heat distortion temperature (HDT) are simultaneously increased by 47.3%, 37.5%, 119.4%, and 59.2% respectively, compared with the pure PDCPD, which synergistically enhances the mechanical properties. [ABSTRACT FROM AUTHOR]

Objectives: Pleiotrophin (PTN), a secreted extracellular matrix‐associated protein, plays an important role in regulating the osteo/dentinogenic differentiation potential of dental pulp stem cells (DPSCs). Our previous study has demonstrated that PTN expression in young DPSCs was is 10‐fold higher than that in aged DPSCs. However, the role of PTN on the in maintaining the stemness of senescent DPSCs remains unclear. The present study aimed to investigate the effect of PTN on senescent DPSCs in vitro. Materials and Methods: Dental pulp stem cells were isolated from human third molars. PTN was knocked down using short hairpin RNAs to study the role of PTN on the senescence of DPSCs. DPSCs with aging performance were obtained by a replicative senescence cell model was obtained by the long‐term culture of DPSCs to the 15th passage in vitro (P15). We then investigated the effect of PTN on senescent DPSCs (P15 DPSCs). Real‐time RT‐PCR, western blotting, alizarin red staining, quantitative calcium analysis, SA‐β‐Gal staining, CFSE, and cell‐counting kit‐8 (CCK8) assays were used to study cellular senescence and function. Results: The depletion of PTN increased the ratio of SA‐β‐gal‐positive cells, upregulated the expression of p16, and down‐regulated the expression of TERT and p‐p38. Furthermore, 50 pg/ml of PTN recombinant protein rescued these changes the altered ratio of SA‐β‐gal‐positive cells, decreased the expression of p16, enhanced TERT and p‐p38 expression, as well as telomere activity, caused by PTN depletion and long‐term culture. The15th passage cells displayed typical aging characteristic, including high ratio of SA‐β‐gal‐positive cells, increased aging‐related gene expression, decreased proliferation rate, high level of Cyclin D expression, and impaired osteo/dentinogenic differentiation potential. However, 50 pg/ml of PTN recombinant protein could partially reverse these alteration rescue these changes. Conclusions: The present study demonstrated that PTN could protect DPSCs from senescence by improving the proliferation and osteo/dentinogenic differentiation ability, probably through the p38 MAPK pathway. [ABSTRACT FROM AUTHOR]

Net-zero entrepreneurship is a novel concept introduced in the context of carbon neutrality, and exploring whether it can catalyze decarbonized economic growth is a worthy pursuit. This study constructs a comprehensive, low-carbon endogenous economic growth model to scrutinize the intricate nexus between net-zero entrepreneurship and decarbonized economic growth. Empirical validation employs a series of multiple regression models to rigorously test the hypotheses derived from the theoretical framework using an extensive dataset spanning Chinese provinces. The results reveal a nuanced landscape. (i) Net-zero entrepreneurship plays a remarkable role in promoting decarbonization growth, with considerable regional heterogeneity. (ii) Green technology progress exhibits a notable mediating effect. (iii) Environmental regulation and industrial structure optimization have positive moderating effects. (iv) The results passed alternative dependent variable and one-phase lag regression robustness tests. In a distinct contribution to entrepreneurship literature, this study augments the discourse on strategies to steer low-carbon transitions. The research findings indicate that net-zero entrepreneurship can accelerate the global decarbonization process, and green technology progress is a significant driving mechanism in this process. Additionally, it is essential to strengthen environmental agencies' regulatory oversight and optimize industrial structures to pave the way for transformative sustainable growth. In the future, more entrepreneurs should be encouraged to engage in green technology and business model innovation to contribute to global decarbonization efforts. [Display omitted] • Net-zero entrepreneurship significantly reduces carbon emission intensity. • Green technology progress mediates entrepreneurship's impact on decarbonized economic growth. • Environmental regulation enhances net-zero entrepreneurship's carbon-reducing effect. • Industrial structure optimization boosts entrepreneurship's decarbonization potential. • Regional heterogeneity exists in net-zero entrepreneurship's impact on decarbonized economic growth. [ABSTRACT FROM AUTHOR]

• Establish a comprehensive evaluation framework for mine ecological restoration. • Use the value added of land assets around the restoration area to assess the social value. • The indirect value of ecological restoration is 3.12 times that of direct value. • Economic-only input–output ratio is 0.34, comprehensive benefit ratio is 1.40. Historical unsustainable mining activities have led to significant ecological degradation, emphasizing the importance and urgency of ecological restoration and its effectiveness assessment. This study evaluates the economic, ecological, and social benefits of ecological restoration in the Longshan mining area from the perspective of ecological product value, utilizing an input–output research framework based on ecosystem service valuation. This comprehensive assessment includes consideration of restoration cost inputs, aiming to delve into the effectiveness of ecological restoration projects in mining areas. The findings reveal: (1) The indirect value of the ecological products generated by the ecological restoration is approximately 3.13 times greater than their direct value, highlighting the significantly positive impacts of the project. This underscores the necessity for future assessments of mining area ecological restoration projects to not only focus on direct economic returns but also to thoroughly examine their long-term positive impacts on social structures, environmental quality, and residents' quality of life. (2) When considered solely from an economic benefit perspective, the input–output ratio of the project is 0.34, insufficient to cover the total cost of the project. However, after integrating economic, ecological, and social benefits, the input–output ratio increases to 1.40. This indicates the importance of exploring the mechanisms through which the indirect values of ecological and social benefits contribute directly to the project's economic sustainability. [ABSTRACT FROM AUTHOR]

• Methyl jasmonate (MeJA) diminished the accumulation of ROS under drought stress. • MeJA improved the photosynthetic capacity and the contents of starch and sucrose. • MeJA promoted nitrogen assimilation and proline accumulation. Drought stress is recognized as one of the foremost abiotic stresses for worldwide agriculture. Methyl jasmonate (MeJA) is a vital phytohormone that is involved in plant growth, development, and stress adaptation. This study aimed to investigate the influence of exogenous MeJA on carbon and nitrogen metabolism in grapevine leaves under drought stress. Two-year-old grape cuttings (Vitis vinifera L.) were foliar sprayed with either 100 μM MeJA solution or distilled water and then exposed to drought stress. The results showed that exogenous MeJA increased the activities of superoxide dismutase (21 %) and catalase (16 %), resulting in decreased accumulation of reactive oxygen species. Drought stress critically disturbed the processes of photosynthesis, sucrose and starch metabolism, nitrogen assimilation, and amino acid metabolism. MeJA pretreatment improved the photosynthetic capacity and decreased the activities of sucrose synthase (31 %), acid invertase (15 %), and neutral invertase (27 %), thereby improving the accumulation of starch (10 %) and sucrose (90 %). In addition, MeJA pretreatment promoted nitrogen assimilation under drought stress. An increase in activities of nitrate reductase (60 %) and glutamine synthetase (13 %), and a decrease in NH 4 + content was observed. Meanwhile, the MeJA application promoted the accumulation of proline and γ-aminobutyric acid, which contributed to the osmotic adjustment and ROS scavenging. In conclusion, exogenous MeJA could promote drought tolerance of grapevines by alleviating oxidative damage and regulating carbon and nitrogen metabolism. [ABSTRACT FROM AUTHOR]