Background Major depressive disorder (MDD) is associated with impaired attention control and alterations in frontal-subcortical connectivity. We hypothesized that attention control as assessed by Stroop task interference depends on white matter integrity in fronto-cingulate regions and assessed this relationship using diffusion tensor imaging (DTI) in MDD and healthy volunteers (HV). Methods DTI images and Stroop task were acquired in 29 unmedicated MDD patients and 16 HVs, aged 18–65 years. The relationship between Stroop interference and fractional anisotropy (FA) was examined using region-of-interest (ROI) and tract-based spatial statistics (TBSS) analyses. Results ROI analysis revealed that Stroop interference correlated positively with FA in left caudal anterior cingulate cortex (cACC) in HVs (r= 0.62, p= 0.01), but not in MDD (r= −0.05, p= 0.79) even after controlling for depression severity. The left cACC was among 4 ROIs in fronto-cingulate network where FA was lower in MDD relative to HVs (F(1,41)= 8.87, p= 0.005). Additionally, TBSS showed the same group interaction of differences and correlations, although only at a statistical trend level. Limitations The modest sample size limits the generalizability of the findings. Conclusions Structural connectivity of white matter network of cACC correlated with magnitude of Stroop interference in HVs, but not MDD. The cACC-frontal network, sub-serving attention control, may be disrupted in MDD. Less cognitive control may include enhanced effects of salience in HVs, or less effective response inhibition in MDD. Further studies of salience and inhibition components of executive function may better elucidate the relationship between brain white matter changes and executive dysfunction in MDD.

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Structural brain deficits are linked to risk for suicidal behavior. However, there is disagreement about the nature of these deficits, probably due to the heterogeneity of suicidal behavior in terms of the suicidal act's lethality. We hypothesized that individuals with major depressive disorder (MDD) and history of more lethal suicide attempts would have lower gray matter volume (GMV) of the prefrontal regions and insula compared with MDD lower-lethality attempters and MDD non-attempters. We collected structural MRI scans on 91 individuals with MDD; 11 with history of higher-lethality suicide attempts, 14 with lower-lethality attempts, and 66 were non-attempters. Differences in GMV between these three groups were examined using both regions-of-interest *

Visible light-driven photocatalysts based on TiO 2 have significant potential for providing sustainable fuel for the future. Layered titanates, which have unique structures, are a focus of considerable research attention due to their ease of interconversion into new nanoarchitectures of TiO 2 that have high photocatalytic performance. We describe here the synthesis of CuO nanostructures from the interconversion of copper titanate during the generation of TiO 2 nanosheets. We further examined the in situ structural transformation of the CuO-loaded TiO 2 nanosheets during photocatalytic hydrogen production from ammonia−borane (NH 3 •BH 3 ; AB) under visible light and studied the impact of the reaction media and of photoirradiation on the catalyst's final structure by characterizing the recovered catalyst using X-ray diffraction (XRD), UV−vis, and transmission electron microscopy (TEM) analyses. The results show that the CuO nanoparticles are converted to metallic Cu nanoparticles, which photocatalyze the reaction through their in situ-formed plasmonic features. The potential role of the introduced plasmonic Cu nanoparticles in promoting charge separation and enhancing photocatalytic performance is also investigated.