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It is important to understand dwell fatigue that has been implicated in several uncontained jet engine failures. Here the authors observe stress bursts due to slip intermittency in a Ti alloy using synchrotron x-ray diffraction microscopy to understand the roles of precipitates and trace oxygen.

Understanding structure-property relationship of dye arrays is of great importance for designing organic photonic and photovoltaic materials. Here, authors present a slip-stacked perylene bisimide array as a model system to investigate singlet fission mechanisms by depending upon interchromophoric interaction.

From earthquakes to hard drives, frictional motion and its strength are involved in a wide range of phenomena. The strength of an interface that divides two sliding bodies is determined by both the real contact area and the contacts' shear strength. By continuous measurements of the concurrent local evolution of the real contact area and the corresponding interface motion from the first microseconds when contact detachment occurs, frictional strength is now characterized from short to long timescales.

Glacier meltwater can penetrate the glacier bed and act as a lubricant, accelerating retreat. Here, the authors use the unique Glacsweb wireless probe at Skálafellsjökull in Iceland and find evidence for two types of stick-slip events: small diurnal events in summer and large multiday events in winter.

Laboratory experiments demonstrate that prior to fast laboratory earthquakes the fault begins to unlock and creep, causing foreshocks to coalesce in both space and time. This demonstrates that the evolution of foreshocks is closely connected to the fault slip velocity.

Residual topography and gravity anomalies reveal a tectonic boundary in northeast Japan, which is proposed to represent the offshore continuation of the Median Tectonic Line; the contrast in frictional properties across this structure may control earthquake behaviour there, as recently demonstrated by the giant 2011 Tohoku-oki earthquake.

Seismic tremors can be used to distinguish plate boundaries. Analysis of tremors occurring deep beneath the San Andreas Fault may identify the boundary between the North American Plate and the preserved remnant of a subducted slab.

A dense network of GPS observations shows that rapid lake drainage events on the western Greenland Ice Sheet are preceded by period of ice-sheet uplift and/or enhanced basal slip.

Both fast and slow earthquakes are preceded by micro-failure events that radiate energy. According to machine learning, these events can foretell catastrophic failure in laboratory experiment earthquakes.

Biological catch bonds counter-intuitively strengthen when pulled. Here, the authors present tuneable artificial catch bonds made from DNA for the study of biomimetic adhesion and the creation of force-strengthening materials.

Deformation of soft colloidal crystals lead to work hardening, similar to that seen in the deformation of metals.

Earthquake instability has long been attributed to fault weakening during accelerated slip, but what are the mechanisms that control this weakening? Here laboratory evidence is presented for the dynamic weakening of faults that are sheared at velocities approaching earthquake slip rates. The experimental faults, made from solid granite blocks, quickly wore to form a fine-grain rock powder, known as gouge, which reduced the faults' strength. It is concluded that only newly formed gouge can weaken the experimental faults.

Despite similarities in crystallography and electronic structure in titanium and zirconium, it is shown that plasticity proceeds differently between the two, associated with differing dislocation configuration stability.

Thendral et al. describe a mitophagic programme that removes deleterious mtDNA during the oocyte-to-zygote transition in Caenorhabditis elegans, promoting mitochondrial health and offspring survival. Loss of this mitophagy leads to mutant mtDNA accumulation.

Findings from a tectonically active mountain range show that soil production is driven by bottom-up rock weakening rather than by soil thickness, challenging long-held top-down models.

Material fatigue is the most common source behind failures of mechanical structures. Here the authors combine transmission electron microscopy, high-resolution electron backscatter diffraction and discrete dislocation plasticity modeling to study the underlying mechanism of dwell fatigue in titanium alloys.

Specific pain-sensing nociceptors and chemosensory tuft cells form a circuit to promote type 2 immune responses in the intestine.

In one earthquake, an oceanic transform fault ruptured in one direction and then backwards at a speed exceeding that of shear-wave propagation, according to an analysis of data recorded by nearby seafloor and global seismometers.

Albumin selectively inhibits Mucorales growth through the release of bound free fatty acids.

Accumulation of interseismic strain may now be constrained by satellite observations. Here, the authors show that strain accumulation rates on the North Anatolian Fault are constant for the interseismic period indicating that lower-crustal viscosities from postseismic studies are not representative.

Metallic microsamples deform in a sequence of abrupt strain bursts. Here, the authors demonstrate by analysing the elastic waves emitted by these bursts that this intermittent process resembles earthquakes in several aspects, although on completely different spatial and temporal scales.

Great Himalayan earthquakes are rare. Analysis of surface motions in the months after the 2015 Gorkha earthquake reveals negligible aseismic slip, implying that stress may be stored in the crust to be tapped during future great earthquakes.

Earthquake breakdown energy is commonly interpreted as a proxy for fracture energy but is observed to scale with magnitude. Here the authors show that a scale-independent stress overshoot, as seen in the 3D dynamic earthquake rupture simulations, leads to comparable scaling despite constant fault fracture energy.

Fluorescence-activated nuclear sorting combined with deep profiling shows that Huntington’s disease repeat expansions arise in specific cell types and are associated with elevated MSH2 and MSH3, which promote expansions in vitro by inhibiting excision of CAG slip-outs by FAN1.

Commercially available bionic hands can replicate many movements, but controlling a multiarticulate bionic hand is not an intuitive task. Here, the authors describe the integration of proximity and pressure sensors into a commercial prosthesis to enable autonomous grasping

The authors used chronic two-photon calcium imaging to record activity in primary whisker somatosensory cortex neurons projecting to secondary somatosensory or primary motor cortex while mice learned a texture discrimination task. Learning-related changes in primary somatosensory cortex enhanced sensory representations in a pathway-specific manner and provided downstream areas with task-relevant information for behavior.

Covalent modification is an essential chemical method for altering the physicochemical properties of material interfaces. Here, the authors show that the no-slip conditions in microfluidic devices grant spatiotemporal control over molecular grafting.

The discovery of slow earthquakes transformed the understanding of how tectonic plate motions are accommodated; however, the mechanics of slow earthquakes remain enigmatic. This Review synthesizes geological observations of ancient deformation structures that likely hosted slow earthquakes and discusses the insights into the mechanics of fault slip.

A diverse array of unusual earthquake phenomena occurring at relatively long periods, 'slow' events, follow a unified scaling relationship that clearly differentiates their behaviour from that of regular earthquakes, indicating that they comprise a new earthquake category.

The impact of grain-scale residual stresses on the mechanical behaviour of 3D-printed metals and alloys remains unexplored. Here, the authors combine in situ synchrotron X-ray diffraction and computer simulations to link residual stresses in steel to its tensile behaviour.

Human T-cell Leukaemia Virus type 1 (HTLV-1) is an untreatable retrovirus that causes cancer and degenerative inflammatory conditions. Here authors describe structures of the HTLV-1 capsid, revealing a target for potential anti-capsid drug development.

A multidisciplinary method for managing triggered seismicity is developed using detailed subsurface information to calibrate geomechanical and earthquake source physics models, and is applied to the Val d’Agri oil field in seismically active southern Italy.

Reduced-activation ferritic-martensitic (RAFM) steels are promising fusion reactor materials having high radiation tolerance and low post-use radioactivity, but achieving high strength, ductility and toughness is difficult. The authors demonstrate a modified thermomechanical process to produce RAFM steel with a multiscale microstructure which endows both high strength and high ductility.

The optokinetic reflex assists image-stabilization in visual systems. Here the authors show that the slow speed preference of ON direction-selective ganglion cells, triggering optokinetic nystagmus, relies on inhibition from VGluT3 amacrine cells.