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Abstract Natural fluctuations in cardiac activity modulate brain activity associated with sensory stimuli, as well as perceptual decisions about low magnitude, near-threshold stimuli. However, little is known about the relationship between fluctuations in heart activity and other internal representations. Here we investigate whether the cardiac cycle relates to learning-related internal representations – absolute and signed prediction errors. We combined machine learning techniques with electroencephalography with both simple, direct indices of task performance and computational model-derived indices of learning. Our results demonstrate that just as people are more sensitive to low magnitude, near-threshold sensory stimuli in certain cardiac phases, so are they more sensitive to low magnitude absolute prediction errors in the same cycles. However, this occurs even when the low magnitude prediction errors are associated with clearly suprathreshold sensory events. In addition, participants exhibiting stronger differences in their prediction error representations between cardiac cycles exhibited higher learning rates and greater task accuracy.

Treatment of hypertension entails use of angiotensin-converting enzyme inhibitors. Here, the authors show a series of karnamicins with significant inhibitory activity and identify two unusual flavoprotein hydroxylases involved in the assembly of the fully-substituted hydroxypyridine core of karnamicins.

Lytic polysaccharide monooxygenases contribute to microbial degradation of chitin, but how the resulting oxidized chitooligosaccharides are utilized by microbes is unclear. Here, the authors describe a complete pathway for oxidative chitin utilization in marine bacteria.

Cocaine is a tropane alkaloid produced by Erythroxylum novogranatense. Here the authors identify two polyketide synthases involved in cocaine biosynthesis and provide insight into the parallel evolution of these enzymes in tropane alkaloids-producing plants.

Tuning of mechanical properties of single composition hydrogel materials and application in integrated devices remains challenging. Here, the authors introduce a macromolecule conformational shaping strategy that enables mechanical programming of polymorphic hydrogel fibre-based devices.

Model systems to study SARS-CoV-2 infection are required to better understand the immune response. Here the authors use a lung and macrophage co-culture system by differentiation of human pluripotent stem cells to better understand the phenotype and gene expression changes in host lung cells and macrophages after SARS-CoV-2 infection in vitro.

The collagenolytic mechanism of Vibrio collagenase, a virulence factor, remains unclear. Here, the authors report the structure of Vibrio collagenase VhaC and propose the mechanism for collagen recognition and degradation, providing new insight into bacterial collagenolysis.

Neointimal hyperplasia and stent thrombosis remain issues with vascular stents. Here, the authors report on the development of a nitric oxide releasing hydrogel which allows for endothelialisation of the stent surface and prevents smooth muscle cell growth reducing hyperplasia and thrombosis in in vivo models.

Here the authors show that 2-aminoethylphosphonate (2AEP) mineralisation is widespread in the global ocean, operating independently of exogenous inorganic phosphate concentration. They propose 2AEP may be a major route for the regeneration of phosphate required to support marine primary production.

Despite the potential of incorporating thermoelectric (TE) fibers into textile electronics for green energy harvesting, existing fabrication methods are not commercially viable. Here, the authors report a scalable gelation extrusion fabrication strategy for realizing alternating p/n-type TE fibers.

Predator-prey interactions play important roles in the cycling of marine organic matter. Here the authors show that a Gram-negative bacterium isolated from marine sediments can kill and feed on Gram-positive bacteria by secreting a peptidoglycan-degrading enzyme.