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Defects in DNA repair frequently lead to neurodevelopmental and neurodegenerative diseases, underscoring the particular importance of DNA repair in long-lived post-mitotic neurons.sup.1,2. The cellular genome is subjected to a constant barrage of endogenous DNA damage, but surprisingly little is known about the identity of the lesion(s) that accumulate in neurons and whether they accrue throughout the genome or at specific loci. Here we show that post-mitotic neurons accumulate unexpectedly high levels of DNA single-strand breaks (SSBs) at specific sites within the genome. Genome-wide mapping reveals that SSBs are located within enhancers at or near CpG dinucleotides and sites of DNA demethylation. These SSBs are repaired by PARP1 and XRCC1-dependent mechanisms. Notably, deficiencies in XRCC1-dependent short-patch repair increase DNA repair synthesis at neuronal enhancers, whereas defects in long-patch repair reduce synthesis. The high levels of SSB repair in neuronal enhancers are therefore likely to be sustained by both short-patch and long-patch processes. These data provide the first evidence of site- and cell-type-specific SSB repair, revealing unexpected levels of localized and continuous DNA breakage in neurons. In addition, they suggest an explanation for the neurodegenerative phenotypes that occur in patients with defective SSB repair. DNA single-strand breaks in neurons accumulate at high levelsin functional enhancers., Author(s): Wei Wu [sup.1] , Sarah E. Hill [sup.2] , William J. Nathan [sup.1] [sup.3] , Jacob Paiano [sup.1] , Elsa Callen [sup.1] , Dongpeng Wang [sup.1] , Kenta Shinoda [...]

To clarify the correlation of single-crystalline structure with corrosion performance in high-strength TiAl alloys, electrochemical and surface characterization was performed by comparing Ti-45Al-8Nb dual-phase single crystals with their polycrystalline counterparts in NaCl solution. Polarization curves show a lower corrosion rate and a higher pitting potential of ∼280 mV for the dual-phase single crystals. Electrochemical impedance spectroscopy and potentiostatic polarization plots revealed a higher impedance of the charge transfer through the compact passive film. Surface composition analysis indicated a compact film with more content of Nb, as twice as that in the film on the polycrystals. Our results reflect that the dual-phase Ti-45Al-8Nb single crystals possess a higher corrosion resistance in NaCl solution, compared with their polycrystalline counterpart, arising from a more homogeneous microstructure and composition distribution. [ABSTRACT FROM AUTHOR]

In this paper, a type of superhydrophobic cotton textile was designed and prepared. Particularly, it was obtained by coating a type of acrylic‐silicone hybrid resin onto the cotton fabric. With self‐stratifying character, the cured coating can be formed into two layers, in which the acrylic component in the bottom layer enables polar bond or hydrogen bond linkage with cellulose molecules on the fiber surface, while the amino silicone oil resin on the surface layer acts as a functional part and adds new surface features to the cotton fabric. As a result, the coated cotton fabric displayed superhydrophobicity, with a water contact angle above 150° and a rolling angle less than 8°. The experimental findings indicated that the fabricated textile had adequate mechanical strength to withstand sandpaper abrasion for 20‐cycles abrasion by pressing a constant load of 500 g. Additionally, the modified textiles exhibited stable oil–water separation abilities, therefore showing multifunctional properties that have potential applications in many cotton textile surface treatments. [ABSTRACT FROM AUTHOR]

The influence and susceptibility of chloride ion concentration, temperature, and surface roughness on corrosion behavior of single‐phase CoCrFeNi medium‐entropy alloy (MEA) was examined in NaCl solution. Potentiodynamic polarization results revealed that the corrosion performance of the sample deteriorated with an increase of the chloride ion concentration, temperature, and surface roughness. The pitting potential decreased drastically for samples with higher surface roughness. According to electrochemical impedance spectroscopy, the charge transfer resistance decreased when chloride ion concentration, temperature, and surface roughness increased. Scanning electron micrographs also indicated an increased extent of corrosion damage, especially for the sample with higher surface roughness. It is found that the corrosion resistance is closely related to the wettability of samples, and the surface with the highest roughness shows higher hydrophilicity. The combined results suggested that the pitting damage is more sensitive to surface roughness. Our findings provide a further understanding of the corrosion mechanism of MEAs and guide their applications as structural materials. [ABSTRACT FROM AUTHOR]