The remediation of uranium-contaminated groundwater via bioreduction coupled to biomineralization with different pH and electron donors.

Stimulating indigenous microbes to reduce aqueous U(VI) to insoluble U(IV) by adding an electron donor has been applied as an applicable strategy to remediate uranium-contaminated groundwater in situ. However, biogenic U(IV) minerals are susceptible to oxidative remobilization after exposure to oxygen. To enhance the stability of the end product, glycerol phosphate (GP) was selected to treat artificial uranium-containing groundwater at different pH values (i.e., 7.0 and 5.0) with glycerol (GY) as the control group. The results revealed that removal ratios of uranium with GP were all higher than those with GY, and reduced crystalline U(IV)-phosphate and U(VI)-phosphate minerals (recalcitrant to oxidative remobilization) were generated in the GP groups. Although bioreduction efficiency was influenced at pH 5.0, the stability of the end product with GP was elevated significantly compared with that with GY. Mechanism analysis demonstrated that GP could activate bioreduction and biomineralization of the microbial community, and two stages were included in the GP groups. In the early stage, bioreduction and biomineralization were both involved in the immobilization process. Subsequently, part of the U(VI) precipitate was gradually reduced to U(IV) precipitate by microorganisms. This work implied that the formation of U-phosphate minerals via bioreduction coupled with biomineralization potentially offers a more effective strategy for remediating uranium-contaminated groundwater with long-term stability.

Harsh Parenting and Children's Aggressive Behavior: A Moderated Mediation Model.

Harsh parenting and its effect on children's aggressive behavior has received attention from researchers, however few studies have considered the role of the emotional process. This study aims to examine the relationship between harsh parenting, children's aggressive behavior, normative beliefs about aggression, and regulatory emotional self-efficacy, alongside their mechanism of interplay. A sample of 235 senior primary school students in Beijing were recruited as participants by using the Harsh Parenting Scale, the Normative Beliefs about Aggression Scale, the Buss-Warren Aggression Questionnaire, and the Regulatory Emotional Self-Efficacy Scale. Results indicated that: (1) Harsh parenting had a significant positive predictive effect on children's aggressive behavior after controlling gender; (2) normative beliefs about the aggression of children mediated the relationship between harsh parenting and children's aggressive behavior; and (3) regulatory emotional self-efficacy had moderating effects both the mediation model of normative beliefs about the aggression of children and in the direct predictive model of harsh parenting on children's aggressive behavior. The results are not only helpful to understand the relationship between harsh parenting and children's aggressive behavior from the perspective of an integrated model of emotion processes and cognition, but also provide a new practical way to prevent and intervene in children's aggressive behavior in the future.