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Background: Severe Acute Respiratory Syndrome coronavirus-2 (SARS-CoV-2) has challenged public health agencies globally. In order to effectively target government responses, it is critical to identify the individuals most at risk of coronavirus disease-19 (COVID-19), developing severe clinical signs, and mortality. We undertook a systematic review of the literature to present the current status of scientific knowledge in these areas and describe the need for unified global approaches, moving forwards, as well as lessons learnt for future pandemics.Methods: Medline, Embase and Global Health were searched to the end of April 2020, as well as the Web of Science. Search terms were specific to the SARS-CoV-2 virus and COVID-19. Comparative studies of risk factors from any setting, population group and in any language were included. Titles, abstracts and full texts were screened by two reviewers and extracted in duplicate into a standardised form. Data were extracted on risk factors for COVID-19 disease, severe disease, or death and were narratively and descriptively synthesised.Results: One thousand two hundred and thirty-eight papers were identified post-deduplication. Thirty-three met our inclusion criteria, of which 26 were from China. Six assessed the risk of contracting the disease, 20 the risk of having severe disease and ten the risk of dying. Age, gender and co-morbidities were commonly assessed as risk factors. The weight of evidence showed increasing age to be associated with severe disease and mortality, and general comorbidities with mortality. Only seven studies presented multivariable analyses and power was generally limited. A wide range of definitions were used for disease severity.Conclusions: The volume of literature generated in the short time since the appearance of SARS-CoV-2 has been considerable. Many studies have sought to document the risk factors for COVID-19 disease, disease severity and mortality; age was the only risk factor based on robust studies and with a consistent body of evidence. Mechanistic studies are required to understand why age is such an important risk factor. At the start of pandemics, large, standardised, studies that use multivariable analyses are urgently needed so that the populations most at risk can be rapidly protected.Registration: This review was registered on PROSPERO as CRD42020177714 . [ABSTRACT FROM AUTHOR]

As the manufactured parts in aerospace and automotive industries tend to be larger and more complex, the inspection process becomes a difficult and timeconsuming one. To decrease inspection costs and time, the optimisation of the required Surface Sampling Points (SSP) is crucial. This paper describes a data sampling technique (DST) for the inspection of waving surfaces of parts. This technique provides the minimum number of SSP required to reconstruct accurately the waving surface. The developed DST comprises two steps: (1) trigonometric polynomial approximation of the curvilinear segments, at certain orthogonal sections on the waving surface, and (2) estimation of the critical frequency of the approximated waving sections, leading to the minimum number of SSP. The pilot implementation of the DST has been performed on a waving wing surface and has been tested using industrial data. The accuracy and the efficiency of the DST has been estimated through (1) the comparison of theoretical (CAD) profiles with the surface profiles measured using the current sampling method and with the ones derived using the developed sampling technique, and (2) the comparison of the sampling intervals extracted by DST and the ones extracted by analysing past measurements with Discrete Fourier Transform (DFT). [ABSTRACT FROM AUTHOR]

Landslide phenomena are strongly affected by physical factors such as the precipitation (mainly rainfall) combined with the geological structure that exists in a region. In addition, the influence of the anthropogenic activities on the natural environment is proven to be a crucial factor in the appearance of geological failures. This study examines the phenomenon of landslides and in particular the distinguishment of those factors which act as an activating cause. In order to achieve this goal three factors were examined as very important. The case study that was investigated was Agrafa Municipality. Rainfall data of fifty year-period, the historical data of landslides in the area and the integrated system of data management system of Geographic Information Systems were used for the evaluation of all these. The models which were developed to achieve the final result are as follows: i) multi-criteria analysis with weighting factors, ii) analytical hierarchy process method and iii) use of same methods without the participation of hydrogeological factors. The results clearly demonstrate the initial belief, as the final hazard maps verify the importance of rainfall in landslides. [ABSTRACT FROM AUTHOR]

The catalytic and electrocatalytic synthesis of ammonia was studied in a proton conducting double-chamber solid electrolyte cell. The BaZrCeYO (BZCY72) proton conducting ceramic was used as the electrolyte with a Ni-BZCY72 cermet and a Pt film serving as cathodic and anodic electrodes, respectively. The reaction was studied at atmospheric pressure and at temperatures between 450 and 700 °C, under both, open- and closed-circuit conditions. A peculiar reaction rate enhancement was observed when the cell returned to open-circuit after operating under closed-circuit for a certain time. A possible explanation of this new phenomenon is that a fraction of protons electrochemically transported to the cathode, is 'stored' in the Ni-BZCY72 electrode in the form of a highly reactive hydride which, upon current interruption, reacts with adsorbed N species to produce ammonia. [ABSTRACT FROM AUTHOR]