Reviews & Analysis

How accurately a person recalls the COVID-19 pandemic is affected by motivational factors, including how they feel about their vaccination status. The recollections of vaccinated and unvaccinated people are skewed in opposite directions, leading to different retrospective narratives about the pandemic. This distorted recall influences how individuals evaluate past political action, and will complicate preparation for future crises.

The neural pathways involved in syncope, or fainting, are not well understood. Studies in mice have identified a defined subset of vagal sensory neurons that connect the heart and brain. Stimulation of these neurons causes reduced heart rate, blood pressure, breathing and neuronal activity in the brain, resulting in syncope.

Many human diseases lack accurate mouse models because it is technically difficult to create extensively genetically humanized mice. A technique that allows large stretches of DNA to be rapidly rewritten in mouse embryonic stem cells can be used to produce improved animal models.

A type of light-sensitive cell in one of the visual systems of fruit flies transmits two chemical messengers, histamine and acetylcholine, in response to the same light signal. These two molecules act on distinct neurons that have different functions: one type creates an image and the other synchronizes biological rhythms with the day–night cycle.

Superconducting detectors are a leading technology for the detection of single photons, but have been limited in the number of pixels that they can offer. A 400,000-pixel superconducting nanowire single-photon detector camera provides an improvement by a factor of 400 compared with the current state of the art.

A single chip that integrates optical and electronic analog computing modules provides a strategy for creating all-analog computing processors with a speed and energy efficiency that are several orders of magnitude higher than those of state-of-the-art digital processors.

Amphibians are the most vulnerable vertebrates worldwide, with 41% of species threatened with extinction. Habitat loss is the most common threat, and climate change is the main driver of increased extinction risk. Investment in amphibian conservation must be scaled up drastically and urgently to prevent further extinctions and reverse declines.

Quantum electrodynamics, the archetypical theory of electromagnetic interactions, describes the behaviour of charged particles and photons using quantum field theory. Measuring the g factor of a bound electron in a hydrogen-like tin ion (¹¹⁸Sn⁴⁹⁺) provides one of the most stringent tests so far of quantum electrodynamics in strong electric fields.

An artificial-intelligence method called deep learning has been used to detect signals of human-induced climate change in daily precipitation data. The results indicate that global warming has increased day-to-day rainfall variability in tropical and mid-latitude regions over the past 40 years.

The gut contents of a fossilized trilobite, Bohemolichas incola, from the Ordovician period (about 465 million years ago), were imaged by a technique called synchrotron microtomography and fully itemized. The results indicate that the animal fed indiscriminately on small shelly invertebrates and that its gut had a neutral to alkaline pH.

A data analysis shows that these destructive tropical storms are shifting earlier in the season all over the globe, owing mainly to anthropogenic climate warming. This seasonal advance could increase the likelihood of the storms overlapping with other extreme weather events, and has implications for disaster prevention.

Precise timekeeping is key to many technologies, motivating the search for more-stable reference oscillators for use as clocks. The resonant X-ray excitation of a long-lived nuclear state in scandium-45 makes it a potential reference oscillator for a nuclear clock that could surpass atomic clocks in stability and resilience against external perturbations.

Air-pollution data from pollution-monitoring stations and satellites show that wildfire smoke has influenced trends in levels of fine particulate matter in nearly three-quarters of the contiguous United States, undoing around 25% of air-quality improvements made between 2000 and 2016. Wildfires are likely to further erode air quality in the country as the climate warms.

T cells that are chronically stimulated in viral infection or cancer enter a dysfunctional state known as T-cell exhaustion. Sympathetic nerves in tissues and tumours drive T-cell exhaustion through the action of the neurotransmitter noradrenaline on the β₁-adrenergic receptors of T cells, with implications for cancer treatment.

The natural toxins portimine A and B have attracted interest for their unusual chemical architecture and potent anti-cancer activity. The first total synthesis of portimines enables the identification of portimine A’s molecular target and reveals that the toxin induces programmed cell death in human cancer cells.

Most high-throughput assays to investigate the role of genes in disease involve in vitro cell models. Now a technology that targets CRISPR–Cas9 gene editing to specific cells in mice, and analyses transcriptional effects in single nuclei, has led to fresh insights into the genes involved in 22q11.2 deletion syndrome.

Plants communicate with neighbouring plants to activate an airborne defence against aphids. However, the genetic pathway underlying this defence mechanism is unknown. A signalling cascade centred around the gaseous form of the chemical methyl salicylate was found to control this interaction between plants.

Electrochemical-reaction pathways in lithium–sulfur batteries have been studied in real time at the atomic scale using a high-resolution imaging technique. The observations revealed an unexpected collective charge-transfer process that could lead to improvements in the performance of these batteries.

Spectroscopy is widely used to characterize samples. Here, spectroscopy of a single molecule of the tropylium cation (C₇H₇⁺) presents a new approach to analysis, particularly for rare or reactive molecular ions that are probably important in interstellar chemistry.

Loss of photons over long-distance connections limits the development of quantum networks, necessitating the use of quantum ‘repeater’ systems to boost signals between network nodes. Erbium ions incorporated into calcium tungstate crystals have been found to emit photons in the telecommunications frequency band that are indistinguishable from each other, and thus show promise for use in such repeaters.