RESUMEN
Coal mining in arid western regions is damaging the fragile ecology, causing problems such as surface damage, vegetation destruction, and soil erosion. These issues are obstacles to the development of green coal, as mining activities can disrupt the distribution of surface vegetation, leading to its spread outside the mining area and affecting surrounding areas. Based on Landsat data, the binary pixel model was used to calculate the vegetation coverage (FVC) in mining area from 2005 to 2021. Through vegetation coverage classification and regression trend analysis, the temporal and spatial changes and evolution trends of vegetation disturbance caused by coal mining and climate were analyzed. Correlation analysis revealed the range of ecological disturbance caused by coal mining at the coal mine scale and mining area scale. The results show that the vegetation coverage of the mining area showed a decreasing trend from 2005 to 2021. Winter and spring precipitation was the primary factor affecting vegetation growth in the area, while coal mining had indirect and secondary effects on vegetation. Human activities played a significant role in improving vegetation, and between 2015 and 2018, the area of vegetation improvement increased by 133.41% compared to that of 2009-2014. Compared to the reference area, the impact range of vegetation disturbance in the mining area is 2.5-5 km, while the impact range of vegetation disturbance in the coal mine is less than 500 m. Therefore, this study provides a theoretical basis for studying the impact of mining activities on vegetation and boundary identification.
Asunto(s)
Minas de Carbón , Monitoreo del Ambiente , China , Plantas , Ecosistema , Conservación de los Recursos NaturalesRESUMEN
Calcium sulfate bone cement (CSC) is extensively used as a bone repair material due to its ability to self-solidify, degradability, and osteogenic ability. However, the fast degradation, low mechanical strength, and insufficient biological activity limit its application. This study used magnesium polyphosphate (MPP) and constructed a composite bone cement composed of calcium sulfate (CS), MPP, tricalcium silicate (C3S), and plasticizer hydroxypropyl methylcellulose (HPMC). The optimized CS/MPP/C3S composite bone cement has a suitable setting time of approximately 15.0 min, a compressive strength of 26.6 MPa, and an injectability of about 93%. The CS/MPP/C3S composite bone cement has excellent biocompatibility and osteogenic capabilities; our results showed that cell proliferation is up to 114% compared with the control after 5 days. After 14 days, the expression levels of osteogenic-related genes, including Runx2, BMP2, OCN, OPN, and COL-1, are about 1.8, 2.8, 2.5, 2.2, and 2.2 times higher than those of the control, respectively, while the alkaline phosphatase activity is about 1.7 times higher. Therefore, the CS/MPP/C3S composite bone cement overcomes the limitations of CSC and has more effective potential in bone repair.
RESUMEN
Stopping postoperative soft tissue adhesions is one of the most challenging clinical problems that needs to be addressed urgently to avoid secondary injury and pain to patients. Currently, membrane materials with anti-protein adsorption and antibacterial activity are recognized as an effective and promising anti-adhesion barrier to prevent postoperative adhesion and the recurrent adhesion after adhesiolysis. Herein, poly(amino acid) (PAA), which is structurally similar to collagen, is selected as the membrane base material to successfully synthesize PAA-5 membranes with excellent mechanical and degradation properties by in-situ melt polymerization and hot-melt film-forming technology. Subsequently, the co-deposition of polydopamine/polysulfobetaine methacrylate (PDA/PSBMA) coatings induced by CuSO4/H2O2on PAA-5 membranes results in the formation of PDC-5S and PDC-10S, which exhibit excellent hemocompatibility, protein antifouling properties, and cytocompatibility. Additionally, PDC-5S and PDC-10S demonstrated significant antibacterial activity againstEscherichia coliandStaphylococcus aureus, with an inhibition rate of more than 90%. As a result, this study sheds light on newly discovered PAA membranes with anti-protein adsorption and antibacterial activity can sever as one of the promising candidates for the prevention of postoperative peritoneum adhesions.