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Gels are used in the oilfield. For example, during oil recovery, organogels are pumped underground into fractures within oil‐bearing rock, so as to block fluid flow. However, after several days, the gels must be degraded (liquefied) to enable oil extraction through the fractures. To degrade gels, ‘degrading agents’ as well as external stimuli have been examined. Here, a concept is demonstrated that avoids external agents and stimuli:self‐degrading organogelsbased on the self‐assembly of molecular gelators. The gels are a) extremely robust (free standing solids) at timet= 0 and (b) degrade spontaneously into a sol after a set timet=t_degrthat can be minutes, hours, or days. These properties are achieved by combining two readily available molecules — the organogelator (1,3:2,4)‐dibenzylidene sorbitol (DBS) and an acid (e.g., hydrochloric acid, HCl) — in an organic solvent. DBS self‐assembles into nanoscale fibrils, which connect into a 3‐D network, thereby gelling the solvent. The acid type and concentration set the value oft_degrat a given temperature. Degradation occurs because the acid slowly hydrolyzes the acetals on DBS, thereby converting DBS into small molecules that cannot form fibrils. DBS gels with a pre‐programmed “degradation clock” can be made with both polar and non‐polar organic solvents. The concept can be a game‐changer for oil recovery as it promises to make it safer, more efficient, and sustainable. 

Prolonged exposure to loud noise has been shown to affect inner ear sensory hair cells in a variety of deleterious manners, including damaging the stereocilia core. The damaged sites can be visualized as ‘gaps’ in phalloidin staining of F-actin, and the enrichment of monomeric actin at these sites, along with an actin nucleator and crosslinker, suggests that localized remodeling occurs to repair the broken filaments. Herein, we show that gaps in mouse auditory hair cells are largely repaired within 1 week of traumatic noise exposure through the incorporation of newly synthesized actin. We provide evidence that Xin actin binding repeat containing 2 (XIRP2) is required for the repair process and facilitates the enrichment of monomeric γ-actin at gaps. Recruitment of XIRP2 to stereocilia gaps and stress fiber strain sites in fibroblasts is force-dependent, mediated by a novel mechanosensor domain located in the C-terminus of XIRP2. Our study describes a novel process by which hair cells can recover from sublethal hair bundle damage and which may contribute to recovery from temporary hearing threshold shifts and the prevention of age-related hearing loss. 

Abstract The semiconductor tracker (SCT) is one of the tracking systems for charged particles in the ATLAS detector. It consists of 4088 silicon strip sensor modules.During Run 2 (2015–2018) the Large Hadron Collider delivered an integrated luminosity of 156 fb -1 to the ATLAS experiment at a centre-of-mass proton-proton collision energy of 13 TeV. The instantaneous luminosity and pile-up conditions were far in excess of those assumed in the original design of the SCT detector.Due to improvements to the data acquisition system, the SCT operated stably throughout Run 2.It was available for 99.9% of the integrated luminosity and achieved a data-quality efficiency of 99.85%.Detailed studies have been made of the leakage current in SCT modules and the evolution of the full depletion voltage, which are used to study the impact of radiation damage to the modules.