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Previous studies have shown that timing of sensory stimulation during the cardiac cycle interacts with perception. Given the natural coupling of respiration and cardiac activity, we investigated here their joint effects on tactile perception. Forty-one healthy female and male human participants reported conscious perception of finger near-threshold electrical pulses (33% null trials) and decision confidence while electrocardiography, respiratory activity, and finger photoplethysmography were recorded. Participants adapted their respiratory cycle to expected stimulus onsets to preferentially occur during late inspiration/ early expiration. This closely matched heart rate variation (sinus arrhythmia) across the respiratory cycle such that most frequent stimulation onsets occurred during the period of highest heart rate probably indicating highest alertness and cortical excitability. Tactile detection rate was highest during the first quadrant after expiration onset. Interindividually, stronger respiratory phase-locking to the task was associated with higher detection rates. Regarding the cardiac cycle, we confirmed previous findings that tactile detection rate was higher during diastole than systole and newly specified its minimum at 250– 300 ms after the R-peak corresponding to the pulse wave arrival in the finger. Expectation of stimulation induced a transient heart deceleration which was more pronounced for unconfident decision ratings. Interindividually, stronger poststimulus modulations of heart rate were linked to higher detection rates. In summary, we demonstrate how tuning to the respiratory cycle and integration of respiratory-cardiac signals are used to optimize performance of a tactile detection task. [ABSTRACT FROM AUTHOR]

Magnetic refrigeration is an upcoming technology that could be an alternative to the more than 100‐year‐old conventional gas–vapor compression cooling. Magnetic refrigeration might answer some of the global challenges linked with the increasing demands for readily available cooling in almost every region of the world and the global‐warming potential of conventional refrigerants. Important issues to be solved are, for example, the required mass and the ecological footprint of the rare‐earth permanent magnets and the magnetocaloric material, which are key parts of the magnetic cooling device. The majority of existing demonstrators use Nd–Fe–B permanent magnets, which account for more than 50% of the ecological footprint, and Gd, which is a critical raw material. This work shows a solution to these problems by demonstrating the world's first magnetocaloric demonstrator that uses recycled Nd–Fe–B magnets as the magnetic field source, and, as a Gd replacement material, La–Fe–Mn–Si for the magnetocaloric heat exchanger. These solutions show that it is possible to reduce the ecological footprint of magnetic cooling devices and provides magnetic cooling as a green solid‐state technology that has the potential to satisfy the rapidly growing global demands. [ABSTRACT FROM AUTHOR]

Retinal dystrophy caused by genetic deficiency of AIPL1 causes severe and rapidly progressive impairment of sight from birth. We sought to evaluate whether early intervention by gene supplementation therapy was safe and could improve outcomes in children with this condition. This non-randomised, single-arm, clinical study conducted in the UK involved four children aged 1·0–2·8 years with severe retinal dystrophy associated with biallelic disease-causing sequence variants in AIPL1. We designed a recombinant adeno-associated viral vector comprising the human AIPL1 coding sequence driven by a human rhodopsin kinase promoter region (rAAV8. hRKp.AIPL1). The product was manufactured under a Specials Licence from the Medicines and Health products Regulatory Authority (UK) and made available to affected children with local ethics approval. We administered the product to one eye of each child by subretinal injection. The children were prescribed oral prednisolone to protect against harm from inflammation. Outcome measures included visual acuity (as assessed with a novel touchscreen test), functional vision (assessed by observing and recording the children's visual behaviour and their ability to perform simple vision-guided tasks), visual evoked potentials (assessed by recording cortical electrophysiological responses to full-screen black-and-white flickering stimuli), and retinal structure (assessed with handheld optical coherence tomography [OCT] and widefield fundus imaging). To identify adverse effects, including inflammation and retinal detachment, we conducted ocular examinations using slit-lamp biomicroscopy and dilated fundoscopy. Safety was further assessed by testing of visual acuity, ophthalmoscopy, handheld OCT and widefield fundus imaging. Patients were selected for treatment between July 12, 2019, and March 16, 2020. Before intervention, the children's binocular visual acuities were limited to perception of light. At a mean of 3·5 years (range 3·0–4·1) after intervention, the visual acuities of the children's treated eyes had improved to a mean of 0·9 logarithm of the minimal angle of the minimum angle of resolution ([logMAR] range 0·8–1·0); visual acuities before intervention were equivalent to 2·7 logMAR. In contrast, the visual acuities of the children's untreated eyes became unmeasurable at the final follow-up. In the two children able to comply with testing, an objective test of visual acuity confirmed improvements in visual function, and measurement of visual evoked potentials showed enhanced activity of the visual cortex, specific to the treated eyes. In three of the children, structural lamination of the outer retina was better preserved in the treated eye than in the untreated eye, and, for all four children, retinal thickness appeared better preserved in the treated eye than in the untreated eye. The treated eye of one child developed cystoid macular oedema. No other safety concerns were identified. Our findings indicate that young children with AIPL1 -related retinal dystrophy benefited substantially from subretinal administration of rAAV8. hRKp.AIPL1 , with improved visual acuity and functional vision and evidence of some protection against progressive retinal degeneration, without serious adverse effects. UK National Institute for Health Research and Moorfields Eye Charity. [ABSTRACT FROM AUTHOR]