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Antibiotic resistance genes (ARGs) are emerging contaminants in the environment and have been highlighted as a worldwide environmental and health concern. As important participants in the biogeochemical cycles, mangrove ecosystems are subject to various anthropogenic disturbances, and its microbiota may be affected by various contaminants such as ARGs. This study selected 13 transects of mangrove-covered areas in Hainan, China for sediment sample collection. The abundance and diversity of ARGs and mobile genetic elements (MGEs) were investigated using high-throughput quantitative polymerase chain reaction (HT-qPCR), and high-throughput sequencing was used to study microbial structure and diversity. A total of 179 ARGs belonging to 9 ARG types were detected in the study area, and the detection rates of vanXD and vatE-01 were 100%. The abundance of ARGs was 8.30 × 107-6.88 × 108 copies per g sediment (1.27 × 10-2-3.39 × 10-2 copies per 16S rRNA gene), which was higher than similar studies, and there were differnd potential hosts of ARGs and provide a scientific basis for the protection and management of Hainan mangrove ecosystem.The presence of phenols, such as nonylphenol (NP), bisphenol (BPA), and octylphenol (OP), in the environment have been receiving increased attention due to their potential risks to human health and environment. The use of reclaimed water for irrigation may be one of the sources of these phenols in the agricultural system. A field experiment was conducted to assess the effects of reclaimed water irrigation on phenol contamination of agricultural topsoil and products in the North China Plain between 2015 and 2016. Three irrigation treatments were applied to all crops reclaimed water irrigation, groundwater irrigation and alternative irrigation with reclaimed water and groundwater (11, v/v). The results showed that the concentrations of NP, BPA, and OP in the topsoil were 0.02-0.54, 0.004-0.06, and ND-9.9 × 10-3 mg/kg, respectively; the corresponding values in agricultural products were 0.007-0.70, 0.004-0.24, and ND-1.08 mg/kg, respectively. The concentration of NP in the topsoil and agricultural products and tFenton reaction is an oxidation process of interest in wastewater treatment because of its ability to degrade organic compounds. Iron-based magnetic particles can be a very useful catalyst when using heterogeneous Fenton process. The major problem of this heterogeneous process is the saturation of the Fe 3+ on the surface, which limits the process. In this study, the possibility of using magnetite particles as a substrate is presented, increasing its degradation efficiency by Fenton reaction through a regeneration process that achieves the electronic reduction of its surface using reducing agents. The results indicate that the regeneration process is quite effective, increasing the efficiency of the degradation of Methylene Blue up to 99%. The concentration of magnetite is the most influential factor in the efficiency of the reaction, while the regeneration time and the concentration of reducing agent do not significantly affect the results considering the range used. The presence of mechanical stirring may adversely affect the reaction in the long term. Increasing the oxidant agent concentration reduces the initial speed of the reaction but not the long-term efficiency. The use of hydrazine in this process allows the successive reuse of these particles maintaining a high percentage of elimination of methylene blue, above 70% even after 10 uses, compared to an elimination below 20% for particles not regenerated after the second use and for particles regenerated with ascorbic acid after the eighth use.Silica nanoparticles (SiNPs) could cause reproductive toxicity. The role of miRNAs in reproductive toxicity induced by SiNPs is still ambiguous. The present study was designed to investigate the role of miRNA-450 b-3p. In vivo, 40 male mice were randomly divided into control, and 20 mg/kg SiNPs groups. selleck products The mice were administrated by tracheal perfusion for 35 days. In vitro, spermatocyte cells (GC-2spd cells) were divided into 6 groups 0 μg/mL SiNPs groups, 5 μg/mL SiNPs groups, 5 μg/mL SiNPs + miRNA-450 b-3p mimic transfection group, 5 μg/mL SiNPs + miRNA-450 b-3p mimic negative control group, 5 μg/mL SiNPs + miRNA-450 b-3p inhibitor transfection group, and 5 μg/mL SiNPs + miRNA-450 b-3p inhibitor negative control group. The results showed that SiNPs induced the apoptosis of spermatogenic cells, decreased the quantity and quality of the sperm, reduced the expressions of miR-450 b-3p, and increased the protein expressions of the MTCH2, BID, BAX, Cytochrome C, Caspase-9, and Caspase-3 in the testis. In vitro, the mimic of miRNA-450 b-3p reversed the decrease of viability and the increase of apoptosis rate and significantly antagonized the expression enhancements of the MTCH2, BID, BAX, Cytochrome C, Caspase-9, Caspase-3 induced by SiNPs, while inhibitor of miRNA-450 b-3p further promoted the effects induced by SiNPs. The result suggested that SiNPs could inhibit the miR-450 b-3p expression resulting in activation of the mitochondrial apoptosis signaling pathways by regulating the MTCH2 in the spermatocyte cells and, thus, induce the reproductive toxicity.Beach litter assessments rely on time inefficient and high human cost protocols, mining the attainment of global beach litter estimates. Here we show the application of an emerging technique, the use of drones for acquisition of high-resolution beach images coupled with machine learning for their automatic processing, aimed at achieving the first national-scale beach litter survey completed by only one operator. The aerial survey had a time efficiency of 570 ± 40 m2 min-1 and the machine learning reached a mean (±SE) detection sensitivity of 59 ± 3% with high resolution images. The resulting mean (±SE) litter density on Saudi Arabian shores of the Red Sea is of 0.12 ± 0.02 litter items m-2, distributed independently of the population density in the area around the sampling station. Instead, accumulation of litter depended on the exposure of the beach to the prevailing wind and litter composition differed between islands and the main shore, where recreational activities are the major source of anthropogenic debris.