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The adsorption of foulants on photocatalytic nanoparticles can suppress their reactivity in water treatment applications by scavenging reactive species at the photocatalyst surface, screening light, or competing for surface sites. These inhibitory effects are commonly modeled using the Langmuir-Hinshelwood model, assuming that adsorbed layer compositions follow Langmuirian (equilibrium) competitive adsorption. However, this assumption has not been evaluated in complex mixtures of foulants. This study evaluates the photoreactivity of titanium dioxide (TiO2) nanoparticles toward a target compound, phenol, in the presence of two classes of foulants ─ natural organic matter (NOM) and a protein, bovine serum albumin (BSA) ─ and mixtures of the two. Langmuir adsorption models predict that BSA should strongly influence the nanoparticle photoreactivity because of its higher adsorption affinity relative to phenol and NOM. However, model evaluation of the experimental phenol decay rates suggested that neither the phenol nor foulant surface coverages are governed by Langmuirian competitive adsorption. Rather, a reactivity model incorporating kinetic predictions of adsorbed layer compositions (favoring NOM adsorption) outperformed Langmuirian models in providing accurate, unbiased predictions of phenol degradation rates. This research emphasizes the importance of using first-principles models that account for adsorption kinetics when assumptions of equilibrium adsorption do not apply. 

As coral reefs face increasing threats from a variety of stressors, coral restoration has become an important tool to aid coral populations. A novel strategy for restoring boulder corals is microfragmentation, which may enhance coral growth by at least five times, depending on species and conditions. However, mortality rates are still significant during the early weeks after transplanting microfragments to impacted areas. We examined the effects of predation after transplanting fragments by cagingOrbicella faveolatamicrofragments and testing if field survival rates would increase after an acclimation period. We tracked the health and growth of ten genotypes across different acclimation periods from a control group of no acclimation (0 months) to full acclimation (4 months). After four months, we presented a mix of acclimated and unacclimated corals to reef predators. Coral survivorship was highest in acclimation cages (near 100%) compared to the field (p < 0.001), with significant growth differences across genotypes (p < 0.001). Microfragments also grew more in acclimation cages (p < 0.001), with rates slowing down in the first two months after being planted into the substrate. Microfragments that had been acclimated for longer than one month also showed comparatively higher survival rates, further supporting the importance of acclimation during restoration. These results suggest caging fragments boost coral survival during initial stages of restoration by > 50% and increase the persistence of transplanted fragments. Results also highlight the importance of identifying and prioritizing genotypes with high survival and growth rates. Beyond coral restoration, results demonstrate the possible negative ecological effects of corallivores, particularly parrotfishes, on recent transplants of fragments. 

Abstract Objective The present study examined whether the effect of neuroticism on brain structure is moderated by behavioral adjustment. Background Neuroticism is widely thought to be harmful to health. However, recent work using proinflammatory biomarkers showed that this effect depends on behavioral adjustment, the willingness and ability to adjust and cope with environmental contingencies, such as different opinions of others or unpredictable life situations. Here, we sought to extend this observation to “brain health” by testing total brain volume (TBV). Method Using a community sample of 125 Americans, we examined structural magnetic resonance imaging of the brain and quantified TBV. We tested whether the effect of neuroticism on TBV was moderated by behavioral adjustment, net of intracranial volume, age, sex, educational achievement, and race. Results Behavioral adjustment significantly moderated the effect of neuroticism on TBV, such that neuroticism was associated with lower TBV only when behavioral adjustment was low. There was no such effect when behavioral adjustment was high. Conclusion The present findings suggest that neuroticism is not debilitating to those who constructively cope with stress. Implications are further discussed. 

Titanium dioxide (TiO 2 ) nanoparticles have been widely studied for water treatment applications; however, natural organic matter (NOM) is often reported to hamper the efficiency of the nanoparticles toward the degradation of target pollutants. Phosphate treatment has been proposed as a potentially facile solution to this problem, as phosphate competes for TiO 2 surface sites to diminish the NOM adsorption. However, the potential importance of the conditions of the NOM exposure and the residual NOM remaining after phosphate treatment have not been fully explored. Here, we investigate the reactivity of phosphate-treated TiO 2 nanoparticles with NOM coatings adsorbed from two background water chemistries, deionized water (TiO 2 –NOM DIW ) and moderately hard water (TiO 2 –NOM MHW ). Thorough characterization by size exclusion chromatography revealed that the adsorbed NOM was only partially displaced after phosphate treatment, with a higher adsorbed mass and wider variety of NOM species persisting on TiO 2 –NOM MHW compared to TiO 2 –NOM DIW . Although the remaining adsorbed NOM did not significantly influence the degradation rate of phenol as a model pollutant, remarkably distinct effects were observed in the degradation of catechol as an oxidative byproduct of phenol, with TiO 2 –NOM MHW hindering catechol degradation and TiO 2 –NOM DIW accelerating catechol degradation. The suppressed reactivity for TiO 2 –NOM MHW was attributed to hindrance of the physical adsorption of catechol to the TiO 2 surface by the NOM MHW layer as well as changes in the reactive oxygen species profile as measured by electron paramagnetic resonance (EPR) spectroscopy, whereas the enhanced reactivity for TiO 2 –NOM DIW was attributed to higher hole formation, suggesting participation of the NOM DIW layer in electron transfer processes. This research highlights the critical importance of the NOM surface coating in directing the mechanisms for pollutant degradation in photocatalytic nano-enabled water treatment applications. 

Abstract In a mesoscale convective system (MCS), convection that redevelops over (i.e., back-builds), and/or repeatedly passes over (i.e., trains) a region for an extended period of time can contribute to extreme rainfall and flash flooding. Past studies have indicated that both mesoscale ascent and lifting of the inflow layer by a cold pool or bore are important when this back-building/training convection is displaced from the leading line [sometimes called rearward off-boundary development (ROD)]. However, Plains Elevated Convection At Night (PECAN) field campaign observations suggest that the stability of the nocturnal boundary layer is highly variable and some MCSs with ROD have only a weak surface cold pool. Numerical simulations presented in this study suggest that in an environment with strong boundary layer stability, ROD can be supported by mechanisms other than those mentioned above. Simulations were initialized using a sounding from ahead of a PECAN MCS with a strong stable layer and ROD, and the three-dimensional simulation produced an MCS similar to that observed despite the homogeneous initial conditions. Some of the findings presented herein challenge existing understanding of nocturnal MCSs, and especially how downdrafts interact with a stable boundary layer. Notably, downdrafts can reach the surface, and different regions of the MCS may have different propagation mechanisms and different relevant inflow layers. Unlike previous studies of ROD, parcel lifting may be supported by an intrusion (an elevated layer of downdraft air) modified by the three-dimensional vertical wind shear.