Iron/titanium oxide-biochar (Fe2TiO5/BC): A versatile adsorbent/photocatalyst for aqueous Cr(VI), Pb2+, F- and methylene blue.

This is the first report of the metal Fe-Ti oxide/biochar (Fe2TiO5/BC) composite for simultaneous removal of aqueous Pb2+, Cr6+, F- and methylene blue (MB). Primary Fe2TiO5 nano particles and aggregates were dispersed on a high surface area Douglas fir BC (∼700 m2/g) by a simple chemical co-precipitation method using FeCl3 and TiO(acac)2 salts treated by base and heated to 80 °C. This was followed by calcination at 500 °C. This method previously was used without BC to make the neat mixed oxide Fe2TiO5, exhibiting a lower energy band gap than TiO2. Adsorption of Cr(VI), Pb(II), fluoride, and MB on Fe2TiO5/BC was studied as a function of pH, equilibrium time, initial adsorbate concentration, and temperature. Adsorption isotherm studies were conducted at 5, 25, and 45 ℃ and kinetics for all four adsorbates followed the pseudo second order model. Maximum Langmuir adsorption capacities for Pb2+, Cr6+, F- and MB at their initial pH values were 141 (pH 2), 200 (pH 5), 36 (pH 6) and 229 (pH 6) mg/g at 45 ℃ and 114, 180, 26 and 210 mg/g at 25 ℃, respectively. MB was removed from the water on Fe2TiO5/BC by synergistic adsorption and photocatalytic degradation at pH 3 and 6 under UV (365 nm) light irradiation. Cr6+, Pb2+, F-, and MB each exhibited excellent removal capacities in the presence of eight different competitive ions in simulated water samples. The removal mechanisms on Fe2TiO5/BC and various competitive ion interactions were proposed. Some iron ion leaching at pH 3 catalyzed Photo-Fenton destruction of MB. Fe2TiO5, BC, and Fe2TiO5/BC bandgaps were studied to help understand photocatalysis of MB and to advance supported metal oxide photodegradation using smaller energy band gaps than the larger bandgap of TiO2 for water treatment. A long range goal is to photocatalytically destroy some sorbates with adsorbents to avoid the need for regeneration steps.

Effortful Control Development in the Face of Harshness and Unpredictability.

Using psychosocial acceleration theory, this multimethod, multi-reporter study examines how early adversity adaptively shapes the development of a self-regulation construct: effortful control. Investigation of links between early life harshness and unpredictability and the development of effortful control could facilitate a nuanced understanding of early environmental effects on cognitive and social development. Using the Building Strong Families national longitudinal data set, aspects of early environmental harshness and early environmental unpredictability were tested as unique predictors of effortful control at age 3 using multiple regression. Early harshness variables were financial harshness, mothers' and fathers' observed parenting, mothers' and fathers' reported use of harsh discipline, and harsh neighborhood conditions. Early unpredictability was measured by number of paternal transitions. Cues of harshness, specifically observed unresponsive parenting, observed harsh parenting, and neighborhood harshness, did significantly negatively predict effortful control. Paternal transitions also significantly predicted effortful control, but in the opposite (i.e., positive) direction. The results corroborate previous research linking quality of parenting to the development of children's effortful control and place it within an evolutionary-developmental theoretical framework. Further, the results suggest that neighborhood harshness may also direct developmental trajectories of effortful control in young children, though the mechanisms through which this occurs are still unclear. This is the first study to explicitly investigate effortful control development in early childhood within the harshness and unpredictability framework.

Potential for Resting-State fMRI of the Amygdala in Elucidating Neural Mechanisms of Adaptive Self-Regulatory Strategies: A Systematic Review.

Evolutionary-developmental theories consider the evolved mechanisms underlying adaptive behavioral strategies shaped in response to early environmental cues. Identifying neural mechanisms mediating processes of conditional adaptation in humans is an active area of research. Resting-state functional magnetic resonance imaging (RS-fMRI) captures functional connectivity theorized to represent the underlying functional architecture of the brain. This allows for investigating how underlying functional brain connections are related to early experiences during development, as well as current traits and behaviors. This review explores the potential of RS-fMRI of the amygdala (AMY) for advancing research on the neural mechanisms underlying adaptive strategies developed in early adverse environments. RS-fMRI studies of early life stress (ELS) and AMY functional connectivity within the frame of evolutionary theories are reviewed, specifically regarding the development of self-regulatory strategies. The potential of RS-fMRI for investigating the effects of ELS on developmental trajectories of self-regulation is discussed.