A DFT study on the adsorption and dissociation of N-Nitrosodimethylamine on a Ni8 nanocluster.

N-Nitrosodimethylamine (NDMA, ONN(CH3)2) is a highly potent carcinogenic investigated by health authorities in some countries. In this manuscript, density functional theory (DFT) is applied to study the NDMA molecular and dissociative adsorption on a Ni8 nanocluster. Molecular adsorption is two times stronger than the NDMA adsorption on the Ni{111} surface. NDMA dissociative adsorption is found more stable than molecular adsorption by ≈1 eV. To dissociate the NDMA molecule into O and NN(CH3)2 fragments, an activation energy is calculated in 0.954 and 0.810 eV from the two most stable molecular configurations. However, to dissociate the NDMA molecule into ON and N(CH3)2 fragments, a smaller activation energy of 0.654 eV is calculated. With the inclusion of the London dispersion forces (optB88-vdW functional), NDMA molecular interactions are a bit stronger. However, the activation energies are slightly smaller. Meta-GGA functional SCAN has also, been applied. The inclusion of the implicit solvation model displays a NDMA weaker interaction with the Ni8 nanocluster. Dissociative adsorption is more stable than molecular adsorption, but the energy difference is a bit smaller, ≈0.850 eV. Present results show that the Ni8 nanoclusters are promising catalysts to NDMA elimination from water.

Alzheimer's disease and alpha-synuclein pathology in the olfactory bulbs of infants, children, teens and adults ≤ 40 years in Metropolitan Mexico City. APOE4 carriers at higher risk of suicide accelerate their olfactory bulb pathology.

There is growing evidence that air pollution is a risk factor for a number of neurodegenerative diseases, most notably Alzheimer's (AD) and Parkinson's (PD). It is generally assumed that the pathology of these diseases arises only later in life and commonly begins within olfactory eloquent pathways prior to the onset of the classical clinical symptoms. The present study demonstrates that chronic exposure to high levels of air pollution results in AD- and PD-related pathology within the olfactory bulbs of children and relatively young adults ages 11 months to 40 years. The olfactory bulbs (OBs) of 179 residents of highly polluted Metropolitan Mexico City (MMC) were evaluated for AD- and alpha-synuclein-related pathology. Even in toddlers, hyperphosphorylated tau (hTau) and Lewy neurites (LN) were identified in the OBs. By the second decade, 84% of the bulbs exhibited hTau (48/57), 68% LNs and vascular amyloid (39/57) and 36% (21/57) diffuse amyloid plaques. OB active endothelial phagocytosis of red blood cell fragments containing combustion-derived nanoparticles (CDNPs) and the neurovascular unit damage were associated with myelinated and unmyelinated axonal damage. OB hTau neurites were associated mostly with pretangle stages 1a and 1b in subjects ≤ 20 years of age, strongly suggesting olfactory deficits could potentially be an early guide of AD pretangle subcortical and cortical hTau. APOE4 versus APOE3 carriers were 6-13 times more likely to exhibit OB vascular amyloid, neuronal amyloid accumulation, alpha-synuclein aggregates, hTau neurofibrillary tangles, and neurites. Remarkably, APOE4 carriers were 4.57 times more likely than non-carriers to die by suicide. The present findings, along with previous data that over a third of clinically healthy MMC teens and young adults exhibit low scores on an odor identification test, support the concept that olfactory testing may aid in identifying young people at high risk for neurodegenerative diseases. Moreover, results strongly support early neuroprotective interventions in fine particulate matter (PM2.5) and CDNP's exposed individuals ≤ 20 years of age, and the critical need for air pollution control.

Systematic and efficient navigating potential energy surface: Data for silver doped gold clusters.

Locating global minimum of certain atomistic ensemble is known to be a highly challenging and resource consuming task. This dataset represents joint usage of the semi-empirical PM7 Hamiltonian, Broyden-Fletcher-Goldfarb-Shanno algorithm and basin hopping scheme to navigate a potential energy surface. The Au20 nanocluster was used for calibration as its global minimum structure is well-known. Furthermore, Au18Ag2 and Au15Ag5 were simulated for illustration of the algorithm performance. The work shows encouraging results and, particularly, underlines proper accuracy of PM7 as applied to this type of heavy metal systems. The reported dataset motivates to use the benchmarked method for studying potential energy surfaces of manifold systems and locate their global-minimum atomistic configurations.