Patients with the COVID-19 condition require frequent and accurate blood oxygen saturation (SpO2) monitoring. The existing pulse oximeters, however, require contact-based measurement using clips or otherwise fixed sensor units or need dedicated hardware which may cause inconvenience and involve additional appointments with the patient. This study proposes a computer vision-based system using a digital camera to measure SpO2 on the basis of the imaging photoplethysmography (iPPG) signal extracted from the human’s forehead without the need for restricting the subject or physical contact. The proposed camera-based system decomposes the iPPG obtained from the red and green channels into different signals with different frequencies using a signal decomposition technique based on a complete Ensemble Empirical Mode Decomposition (EEMD) technique and Independent Component Analysis (ICA) technique to obtain the optical properties from these wavelengths and frequency channels. The proposed system is convenient, contactless, safe and cost-effective. The preliminary results for 70 videos obtained from 14 subjects of different ages and with different skin tones showed that the red and green wavelengths could be used to estimate SpO2 with good agreement and low error ratio compared to the gold standard of pulse oximetry (SA210) with a fixed measurement position.

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Head injury in childhood is the single most common cause of death or permanent disability from injury. However, despite its frequency and significance, there is little understanding of the response of a child's head to injurious loading. This is a significant limitation when making early diagnoses, informing clinical and/or forensic management or injury prevention strategies. With respect to impact vulnerability, current understanding is predominantly based on a few post-mortem-human-surrogate (PMHS) experiments. Researchers, out of experimental necessity, typically derive acceleration data, currently an established measure for head impact vulnerability, by calculation. Impact force is divided by the head mass, to produce a "global approximation", a single-generalised head response acceleration value. A need exists for a new experimental methodology, which can provide specific regional or localised response data. A surrogate infant head, was created from high resolution computer tomography scans with properties closely matched to tissue response data and validated against PMHS head impact acceleration data. The skull was 3D-printed from co-polymer materials. The brain, represented as a lumped mass, comprised of an injected gelatin/water mix. High-Speed Digital-Image-Correlation optically measured linear and angular velocities and accelerations, strains and strain rates. The "global approximation" was challenged by comparison with regional and local acceleration data. During impacts, perpendicular (at 90°) to a surface, regional and local accelerations were up to three times greater than the concomitant "global" accelerations. Differential acceleration patterns were very sensitive to impact location. Suture and fontanelle regions demonstrated ten times more strain (103%/s) than bone, resulting in skull deformations similar in magnitude to those observed during child birth, but at much higher rates. Surprisingly, perpendicular impacts produced significantly greater rotational velocities and accelerations, which are closer to current published injury thresholds than expected, seemingly as a result of deformational changes to the complex skull geometry. The methodology has proven a significant new step in characterising and understanding infant head injury mechanics.

Chronic Traumatic Encephalopathy (CTE) affects a significant portion of athletes in contact sports but is difficult to quantify using clinical examinations and modelling approaches. We use an in silico approach to quantify CTE biomechanics using mesoscale Finite Element (FE) analysis that bridges with macroscale whole head FE analysis. The sulci geometry produces complex stress waves that interact with each another to create increased shear stresses at the sulci depth that are significantly larger than in analyses without sulci (from 0.5 kPa to 18.0 kPa). Also, Peak sulci stresses are located where CTE has been experimentally observed in the literature.

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