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Understanding the mechanical behaviour of jointed rock during seismic events is crucial for ensuring the stability of rock engineering. A series of uniaxial compression tests were conducted on granite specimens containing a persistent joint at strain rates (10−5–0.05/s). Acoustic emissions (AEs) were monitored to detect the rock fracturing, and the strain field on the specimen surface was measured by the digital image correlation technique. Three failure patterns of specimens were observed: rock splitting, joint slipping and mixed rock splitting–joint slipping. The shapes of typical strain–stress curves for the three patterns are different, but they are all characterised by multiple stress drops indicating significant rock fractures. When significant fractures occur, the frequency range of AEs expends and the dominant frequency of AEs becomes much larger. The specimen strength is affected by the strain rate, but this effect differs for different failure patterns of specimens. The joint inclination could influence the mode and profile of fractures near the joint, and the specimen strength and joint stiffness significantly decrease with increasing joint angle. This study could help better understand the behaviour of jointed rocks subjected to seismic loads. [ABSTRACT FROM AUTHOR]

As a significant organelle in cells, endoplasmic reticulum is a cystic, vesicular and tubular structure formed by a single unit membrane. Herein, we develop an endoplasmic reticulum (ER)-targeting NIR probe, HL-Cys, for Cys, which has ratiometrically fluctuating UV-vis absorption and fluorescence spectra with large Stokes shift, with desirable selectivity and sensitivity. Biological imaging demonstrates that HL-Cys could locate in the ER and image Cys levels during ER oxidative stress in HeLa cells. [ABSTRACT FROM AUTHOR]