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[Display omitted] • Bioleaching conditioning mitigated ARGs in sludge compost products. • Bioleaching conditioning led to the lowest abundances of ARG-associated bacteria. • ARGs Shift during bioleached sludge composting can be ascribed to potential hosts. • Pre-removal of ARGs is crucial for the ARGs reduction in bioleached sludge compost. • Possible limited horizontal transfer of ARGs also contributed to their reduction. Conditioning can drastically improve the dewaterability of sewage sludge and is widely practiced in most wastewater treatment plants (WWTPs). Sludge conditioning was also reported as a crucial step in sludge treatment to attenuate antibiotic resistance, but it remains unclear whether the attenuated antibiotic resistance by conditioning treatments would guarantee low abundance of antibiotic resistance genes (ARGs) in the compost products of municipal sewage sludge. Herein, the impacts of three conditioning treatments, including bioleaching and chemical conditioning using Fe[III]/CaO or polyacrylamide (PAM), on the abundances of 20 ARGs and 4 mobile genetic elements (MGEs) during conventional aerobic composting of dewatered sludge were investigated. It was found that the absolute and relative abundances of total ARGs in compost product of bioleached sludge accounted for only 13.8%-28.8% of that in compost products of un-conditioned, Fe[III]/CaO-conditioned, or PAM-conditioned sludges. Besides, bioleaching conditioning resulted in the lowest abundances of ARG subtypes and ARG-associated bacteria in the sludge compost product. The shift of ARG profiles in the bioleached sludge composting can be mainly ascribed to the ARG-associated bacteria, while the MGEs drove the ARG profiles during conventional composting of un-conditioned sludge and the two chemically conditioned sludge. Thus, bioleaching conditioning is superior to the chemical conditioning using Fe[III]/CaO or PAM in mitigating antibiotic resistance in sludge compost products, which was contributed by the pre-removal of ARGs prior to composting treatment and the potential limitation of ARGs transfer during conventional composting. [ABSTRACT FROM AUTHOR]

Schwertmannite, jarosite or goethite are commonly used to remove metals and/or metalloids from contaminated water via adsorption processes, but it is still unclear whether they can be used as adsorbents to remove hydrophobic organic pollutants (HOCs), such as polycyclic aromatic hydrocarbons (PAHs), from groundwater or wastewater. Here, the feasibility of using these iron (oxyhydr) oxide minerals as adsorbents for phenanthrene (a model PAH) adsorption and regenerating the spent adsorbents via heterogeneous Fenton-like reaction was investigated. Results showed that they exhibited rapid adsorption rates and considerable adsorption capacities for phenanthrene. The maximum Langmuir capacities (Qmax) for phenanthrene adsorption at 28 °C were in an ascending order of goethite (567 μg·g-1) < schwertmannite (727 μg·g-1) < jarosite (2088 μg·g-1). The adsorption process was a spontaneous and exothermic process along with the decrease of randomness at the solid/liquid interfaces, which was influenced by temperature, adsorbent dosage, and the coexistence of inorganic anions. Both schwertmannite and jarosite were superior to goethite in light of their easy separation from the bulk solution after the adsorption processes. A multi-cycle experiment demonstrated that the regeneration efficiency of schwertmannite (97.9–99.7%) was much higher than that of jarosite (80.1–87.2%), and the mineral structure, morphology and functional groups of schwertmannite were not changed during the successive adsorption-regeneration processes. Therefore, among the investigated three iron (oxyhydr) oxide minerals, schwertmannite was an attractive and regenerable adsorbent for the removal of phenanthrene from water owing to its high adsorption capacity, good separation ability, and excellent reusability. Image 1 • Schwertmannite, jarosite and goethite can rapidly adsorb phenanthrene. • The adsorption process was a spontaneous and exothermic process. • Schwertmannite and jarosite had better separation ability than goethite. • The regeneration efficiency of schwertmannite was as high as 97.9–99.7%. [ABSTRACT FROM AUTHOR]

The East Asian summer precipitation exhibits significant spatial differences from inter-annual to sub-orbital timescales, which has been associated with El Niño-Southern Oscillation (ENSO). However, studies on spatial patterns of climate and their mechanisms on orbital and tectonic timescales are still scarce, impeding a better understanding of Asian monsoon dynamics on long timescales. Here, we present a loess section spanning the past 430 ka in the Menyuan (MY) basin from the Northeastern Tibetan Plateau (NETP), and compare it with records from other sites in East Asia in order to explore the spatial patterns of climate changes and their mechanisms. Our results reveal a distinct climate transition at ∼260 ka in various records, which is characterized a transition from a "wet–dry–wet" to a "dry–wet–dry" pattern in the north-south direction and a transition from a "dry–wet" to "wet–dry" pattern in the west-east direction. This climate transition coincides with a significant weakening of the equatorial Pacific zonal (east–west) thermal gradient which indicates a shift to a more El Niño-like state, suggesting that the climate transition in East Asia at ∼260 ka could be related to paleo-ENSO variation. A more El Niño-like state could force an intensification and southwestward extension of the Western Pacific Subtropical High (WPSH) which could in turn move the rainfall front westward with the maximum rainfall belt over central China, resulting in the persistence of the observed climate patterns in East Asia. Our model results suggest that the change of the paleo-ENSO condition at ∼260 ka could be related to the eccentricity-modulated insolation and the ice shelve changes in northern high latitudes. Our study highlights the important role of paleo-ENSO in regulating the long-term climate changes in different sub-regions in East Asia. • The East Asian monsoon region is divided into four sub-regions. • A transition of meridional tripole climate pattern in East Asia occurred at ∼260 ka. • A transition of zonal dipole climate pattern existed in mid-latitude monsoonal region. • Paleo-ENSO was the dominant forcing for the ∼260 ka climate transition. • Paleo-ENSO may be influenced by changes in eccentricity and Arctic ice shelves. [ABSTRACT FROM AUTHOR]

Basic region/leucine zipper (bZIP) transcription factors function as critical regulators in numerous abiotic stress responses. Massive bZIPs have been systematically identified in plants, but not in sweetpotato. In this study, 87 sweetpotato IbbZIPs unevenly distributed onto 15 chromosomes were identified, and segmental duplications were shown to play dominant roles in the diversity of IbbZIPs. The collinearity between IbbZIPs and the related orthologs from nine plants depicted evolutionary insights into bZIP gene family. Additionally, IbbZIP proteins were clustered into 11 subfamilies while no members were found in the M subfamily, and the regularity of gene structures and conserved motifs was consistent with the subgroup classification. Evidence from transcriptome data and qRT-PCR analysis of 12 selected IbbZIPs revealed that they were significantly and varyingly induced under multiple abiotic stresses (salt, drought, heat and cold) and hormone treatments (ABA, ACC, JA and SA). Consistently, the promoters of IbbZIPs harbored multiple stress- and hormone-related cis-acting elements. Besides, IbbZIP17 and IbbZIP61 exhibited transactivation activity in yeasts, while IbbZIP-14/-69/-84 did not. These findings supply worthy foundations for further functional investigation of IbbZIPs , and multiple members may serve as promising regulators to enhance the abiotic stress tolerance of transgenic plants. [ABSTRACT FROM AUTHOR]

• 175 sweetpotato IbANCs were identified and clustered into 22 subgroups including 4 specific subgroups. • Tandem duplications and segmental duplications played critical roles in the diversity of IbANCs. • Collinearity between IbANCs and related orthologs from other plants depicted evolutionary insights into NACs. • Transcriptome and qRT-PCR data provided multiple promising IbNAC regulators for breeding tolerant sweetpotato. • IbNAC006 and IbNAC143 exhibited transactivation activities in yeasts. Sweetpotato is a pivotal crop that can tolerate various edaphic and climatic conditions. The plant-specific NAC transcription factors are involved in regulating various adverse environmental conditions, while currently NAC genes have not been systematically characterized in sweetpotato. Herein, 175 putative NAC or NAC-like genes (IbNACs) were identified in sweetpotato. These genes were unevenly scattered onto all 15 chromosomes, among which 12 pairs of tandem duplications and 12 groups of fragment duplications existed. The collinearity analysis between IbNACs and the related orthologs from nine other plant species further depicted evolutionary insights into NAC gene family. Phylogenetic analysis displayed that IbNAC proteins were classified into 22 subfamilies including four sweetpotato-specific subfamilies, with the support of gene structure and motif analyses. Transcriptome analysis showed that IbNAC genes differed significantly in expression under salt stress, and significant and varying expression of ten selected genes under multiple abiotic stresses was detected by qRT-PCR. Moreover, IbNAC006 and IbNAC143, which were significantly induced by abiotic stress, exhibited obvious transactivation activities, while IbNAC-029/-138/-148 did not. These results will lay the foundation for further evolutionary analysis and functional characterization of IbNACs , particularly with regards to the potential applications of multiple IbNAC regulators in the breeding of tolerant sweetpotato. [ABSTRACT FROM AUTHOR]