Novel polyurethane acrylates (PUAs) were prepared by the reaction of soy polyols with isophorone diisocyanate and hydroxyethylacrylate. FTIR results confirmed the formation of PUAs from different kinds of soy polyols. The glass transition, damping properties, thermal stabilities, and mechanical properties of PUAs were characterized by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and universal test machine. The morphology of PUAs was investigated by scanning electron microscope (SEM). The results of the swelling experiments showed that the crosslinking density of polyurethanes and PUAs directly correlated with the hydroxyl (OH) number of polyols. The DSC and DMA results displayed that the glass transition temperature of PUAs was higher than that of polyurethanes and increased with OH number. Furthermore, the formation of PUA networks improved the damping properties of polyurethanes. TGA results demonstrated the acrylation of polyurethanes improved its thermal stability. The initial decomposition temperature of polyurethanes and PUAs also increased with OH number. When compared with polyurethanes, the tensile strengths of PUAs were improved by 118%, 39%, and 9%, respectively, with the increase of OH number of three soy polyols.

Osteosarcoma is a malignant tumor derived from the skeletal system, often occurring in bone tissues, and it is the most common malignant tumor in the skeletal system, with more than 90% of cases being highly malignant. The present study was designed to explore the regulatory effects of microRNA (miR)-19a on the proliferation and apoptosis of osteosarcoma cells, and its influence on the activation of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. The expression of miR-19a in adult SaOS-2 osteosarcoma cells was downregulated via lentiviral transfection, and the cells were divided into a control group, NC-inhibitor group and miR-19a-inhibitor group. The expression of miR-19a in each group was detected via quantitative polymerase Chain reaction (qPCR). Next, the cell proliferation and apoptosis levels in each group were detected via methyl thiazolyl tetrazolium (MTT) assay and flow cytometry, respectively, and the level of reactive oxygen species (ROS) in cells was further determined. Moreover, the expression levels of apoptosis-related proteins and JAK2/STAT3 signaling pathway-related proteins were detected through western blotting. The expression level of miR-19a in the miR-19a-inhibitor group was significantly lower than that in the control group and NC-inhibitor group (P<0.01). Downregulation of miR-19a significantly reduced the proliferation ability (P<0.01), increased the apoptosis level of SaOS-2 cells (P<0.01), and significantly increased the ROS level in cells (P<0.01). Downregulation of miR-19a also promote cleaved caspase-3/caspase-3 expression in the OS cells (P<0.01) and inhibited Bcl-2/Bax expression (P<0.01). Additionally, downregulation of miR-19a markedly lowered the protein expression levels of phosphorylated (p-)JAK2, p-STAT3 and myeloid cell leukemia-1 (Mcl-1) in the cells (P<0.01). To conclude, downregulation of miR-19a can inhibit the JAK2/STAT3 signaling pathway in SaOS-2 cells, promote the expression of apoptosis-related proteins, and increase the ROS level in cells, thereby promoting apoptosis and inhibiting cell proliferation.

With the increasing frequency of extreme weather events, promoting crop production's resilience to combat climate disaster is urgent for global food security, however, the driving factors of crop production's resilience are not yet clear to figure out the effective measures to improve it. At the same time, the benefits of agricultural mechanization, especially on resilience are not fully adopted, which may offer solutions for climate change adaptation. Here, we propose a crop production's climate resilience driving factors assessment framework based on modified Pressure-State-Response concept and two-way fixed effect model. Taking China as the study area, we figure out the spatio-temporal evolution of crop production's climate resilience and analyze the effect of rapidly developed agricultural mechanization on it. Our primary results show that food production's climate resilience in China has been promoted since 2005, although drought and flooding events are gradually becoming more frequent. Complementarity among Chinese provinces enhances overall national food production's climate resilience, to which Jilin Province and Xinjiang Province contributed the most. Due to timely policy adjustments, the autumn harvest has played an increasingly important role in enhancing resilience. Besides, agricultural mechanization played a significant role in guaranteeing food productivity to tackle climate impact. By analyzing the effect of agricultural mechanization on food production's climate resilience in China, this study can provide insights for strengthening agriculture sector's resilience and thus avoiding disruptions in food supply chains.