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[Display omitted] • The influences of environmental factors on the dissemination of airborne ARGs were investigated. • The fecal contribution to airborne bacteria is 19.9% and 59.4% in pig farms during summer and winter. • Horizontal gene transfer plays an important role during winter in pig farms atmosphere. • The transmission routes and the control strategy of airborne ARGs are described in pig farms. Although pig farms are hotspots of antibiotic resistance due to intensive use of antibiotics, little is known about the abundance, diversity and transmission of airborne antibiotic resistance genes (ARGs). This study reports that bioaerosol is an important spread route of ARGs in pig farms. ARGs, mobile genetic elements (MGEs), and bacterial communities were investigated in both air and feces samples during winter and summer. The average concentration of airborne ARGs and MGEs during winter is higher than that during summer when using the ventilation system. The tet M is identified as the predominant airborne ARG with abundance of 6.3 ± 1.2 log copies/m3. Clostridium and Streptococcus are two dominant bacteria and several opportunistic pathogens are detected in air samples. High temperature is favorable for more diverse bacterial communities, but relative humidity has negative effects. The wind speed promotes the spread of airborne ARGs. The network analysis results show the average fecal contribution to airborne bacteria is 19.9% and 59.4% during summer and winter, respectively. Horizontal gene transfer plays an important role in the dissemination of airborne ARGs during winter (77.8% possibility), while a lower possibility of 12.0% in summer. [ABSTRACT FROM AUTHOR]

• Novel enhanced-macroporous anode was fabricated for flow-through electrochemical process. • The anode has excellent electrochemical property and degradation performance. • Optimization of flow-through anode was studied for further porous anodes design. • Degradation contribution of radical oxidation and nonradical oxidation was quantitatively analyzed. • The energy efficiency comparison of MIT degradation were investigated. This paper reports on the development of macroporous flow-through anodes. The anodes comprised an enhanced TiO 2 nanotube array (ENTA) that was grown on three macroporous titanium substrates (MP-Ti) with nominal pore sizes of 10, 20, and 50 µm. The ENTA was then covered with SnO 2 -Sb 2 O 3. We refer to this anode as the MP-Ti-ENTA/SnO 2 -Sb 2 O 3 anode. The morphology, pore structure, and electrochemical properties of the anode were characterized. Compared with the traditional NTA layer, we found that the MP-Ti-ENTA/SnO 2 -Sb 2 O 3 anode has a service lifetime that was 1.56 times larger than that of MP-Ti-NTA/SnO 2 -Sb 2 O 3. We used 2-methyl-4-isothiazolin-3-one (MIT), a common biocide, as the target pollutant. We evaluated the impact of the operating parameters on energy efficiency and the oxidation rate of MIT. Furthermore, the apparent rate constants were 0.38, 1.63, and 1.24 min−1 for the 10, 20, and 50 μm nominal pore sizes of the MP-Ti substrates, respectively, demonstrating the different coating–loading mechanisms for the porous substrate. We found that hydroxyl radicals were the dominant species in the MIT oxidation in the HO radical scavenging experiments. The radical and nonradical oxidation contributions to the MIT degradation for different current densities were quantitatively determined as 72.1%–74.8% and 25.2%–27.9%, respectively. Finally, we summarized the oxidation performance for MIT destruction for (1) the published literature on various advanced oxidation technologies, (2) the published literature on various anodes, and (3) our flow-by and -through anodes. Accordingly, we found that our flow-through anode has a much lower electrical efficiency per order value (0.58 kWh m−3) than the flow-by anodes (6.85 kWh m−3). [ABSTRACT FROM AUTHOR]