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Intracranial pressure (ICP) monitoring is important in managing neurosurgical, neurological, and ophthalmological patients with open-angle glaucoma. Non-invasive two-depth transcranial Doppler (TCD) technique is used in a novel method for ICP snapshot measurement that has been previously investigated prospectively, and the results showed clinically acceptable accuracy and precision. The aim of this study was to investigate possibility of using the ophthalmic artery (OA) as a pressure sensor for continuous ICP monitoring. First, numerical modeling was done to investigate the possibility, and then a pilot clinical study was conducted to compare two-depth TCD-based non-invasive ICP monitoring data with readings from an invasive Codman ICP microsensor from patients with severe traumatic brain injury. The numerical modeling showed that the systematic error of non-invasive ICP monitoring was < 1.0 mmHg after eliminating the intraorbital and blood pressure gradient. In a clinical study, a total of 1928 paired data points were collected, and the extreme data points of measured differences between invasive and non-invasive ICP were − 3.94 and 4.68 mmHg (95% CI − 2.55 to 2.72). The total mean and SD were 0.086 ± 1.34 mmHg, and the correlation coefficient was 0.94. The results show that the OA can be used as a linear natural pressure sensor and that it could potentially be possible to monitor the ICP for up to 1 h without recalibration.

A simplified model of Covid-19 epidemic dynamics under quarantine conditions and method to estimate quarantine effectiveness are developed. The model is based on the growth rate of new infections when total number of infections is significantly smaller than population size of infected country or region. The model is developed on the basis of collected epidemiological data of Covid19 pandemic, which shows that the growth rate of new infections has tendency to decrease linearly when the quarantine is imposed in a country (or a region) until it reaches constant value, which corresponds to the effectiveness of quarantine measures taken in the country. The growth rate of new infections can be used as criteria to estimate quarantine effectiveness.

Gasification of wood pellets is confronted with the problem of adhesion of fuel in the pyrolysis zone. In order to investigate the cause and regularities of fuel adhesion, experimental and theoretical studies of wood pellets thermal deformations were carried out. Experimental studies were performed by measuring thermal deformation of a wood pellet in an electrical reactor from 300 to 1 000 °C temperature in an inert atmosphere. The studies showed that the pellet radius decreased by 10% from 300 to 500 °C temperature, and by 20% from 500 to 1 000 °C temperature. It was also es tablished that the wood pellet expands to 15% from 300 to 830 °C temperature at the beginning of fuel thermal deformation.The paper also presents the theoretical studies of wood pellets thermal defor mations. The theoretical calculations were performed by Matlab using a onedi men sional pyrolysis model of wood pellets that includes the experimental data and the observed expansion of wood pellets. Simulation results were compared with the experimental ones. Modelling and experimental results showed that the thermal deformation of wood pellets values was different by 2-5%.