Pits and adatoms at the interface of 1-ML C ₈₄ /Ag (111)

Abstract

We prepare a well-defined C84 monolayer on the surface of Ag (111) and study the geometric structure by scanning tunneling microscopy (STM). The C84 molecules form a nearly close-packed incommensurate R30° lattice. The lattice is long-distance ordered with numerous local disorders. The monolayer exhibits complex bright/dim contrast; the largest height difference between the molecules can be greater than 0.4 nm. Annealing the monolayer at 380 °C can desorb part of the molecules, but more than sixty percent molecules stay on the Ag (111) surface even after the sample has been annealed at 650 °C. Our analyses reveal that the 7-atom pits form beneath many molecules. Some other molecules sit at the 1-atom pits. Ag adatoms (those removed substrate atoms, accompanying the pit formation) play a very important role in this system. The adatoms can either stabilize or destabilize the monolayer, depending on the distribution manner of the adatoms at the interface. The distribution manner is determined by the co-play of the following factors: the dimension of the interstitial regions of the C84 overlayer, the number of the adatoms, and the long-distance migration of part adatoms.

Editorial: World digestive health day: investigating the link between neurodegenerative disease and gut microbiota

“…The BBB's integrity is harmed by the secretion of biomolecules from gut microbiota, which worsens with increased dysbiosis. The gut microbiota contains beneficial bacteria that help maintain redox homeostasis, while dysregulation of the gut microbiota has been strongly associated with the development of oxidative stress-mediated NDs (Wang et al, 2022). These findings suggest that modulation of AD through dietary and gut microbiota interventions may be potential therapeutic strategies.…”

“…Certain bacteria in the human gut, including Staphylococcus aureus, Escherichia coli, Salmonella, Mycobacterium, Klebsiella pneumoniae, and Streptococcus, promote the production and aggregation of amyloid-β (Aβ) protein in the enteric nervous system (Wu et al, 2021). The bacterial amyloid protein produced by coccus-shaped bacteria can activate the innate immune system, triggering responses by Toll-like receptors and cluster of differentiation 14, resulting in inadequate recognition of misfolded Aβ and decreased Aβ clearance, followed by the production of cytokines leading to intestinal disturbances (Wang et al, 2022). Dysregulation of the gut microbiota leads to oxidative stress, inflammation, disruption of the blood-brain barrier (BBB), activation of the immune system, neurofibrillary tangles, and Aβ plaques followed by neurodegeneration (Wang et al, 2022).…”

“…The bacterial amyloid protein produced by coccus-shaped bacteria can activate the innate immune system, triggering responses by Toll-like receptors and cluster of differentiation 14, resulting in inadequate recognition of misfolded Aβ and decreased Aβ clearance, followed by the production of cytokines leading to intestinal disturbances (Wang et al, 2022). Dysregulation of the gut microbiota leads to oxidative stress, inflammation, disruption of the blood-brain barrier (BBB), activation of the immune system, neurofibrillary tangles, and Aβ plaques followed by neurodegeneration (Wang et al, 2022). The BBB's integrity is harmed by the secretion of biomolecules from gut microbiota, which worsens with increased dysbiosis.…”

Sustainable theory of a logistic model - Fisher information approach

“…Many researchers have extended the logistic model to include perturbations in the model parameters for feedback by periodic or random modulation (e.g. [4,5,6,7,8,9,10,11]) or to couple to the evolution of other systems (e.g. [12]).…”