REMOTE PULSE OXIMETRY IMAGING – FUNDAMENTALS AND APPLICATIONS

The remote photoplethysmography imaging (PPGI) system is a camera-based monitoring device for non-contact analysis of skin perfusion allowing measurement of vital parameters, like heart rate and respiration rate. PPGI is based on the same principle as classic photoplethysmography (PPG), i.e. measurement of optical absorption and scattering properties of skin. Pulse oximetry is a well-established clinical application of PPG to determine arterial blood oxygenation and this has been adapted for use with the PPGI setup. We describe the theoretical correlation between the measurement results and expected level of oxygen saturation. The feasibility of the proposed system is demonstrated by confirming the theory with results from tests with human volunteers in a laboratory setting and in an operating theatre during an ongoing (clinical) animal trial. Compared with measurement devices based on skin contact, the PPGI offers several advantages. It allows unobtrusive remote measurement as well as evaluation of vital parameters with spatial resolution. Therefore, PPGI is particularly suited for long-term monitoring of freely selectable and potentially sensitive skin regions, e.g. for preterm neonates being cared for in an incubator

Assessment of Human Hemodynamics under Hyper- and Microgravity: Results of two Aachen University Parabolic Flight Experiments

Astronauts complain about fluid shifts from their lower extremities to their head caused by weightlessness during their flight into space. For a study of this phenomenon, RWTH Aachen University and Charité University Berlin participated in a joint project on two parabolic flight campaigns of the German Aerospace Centre (DLR) in September 2005 and June 2006. During these campaigns, the characteristics of the rapid fluid shifts during hyper- and micro gravity were measured by a combination of PPG and PPGI optoelectronic sensor concepts.

Rapid detection of methicillin-resistant Staphylococcus aureus directly from clinical samples: methods, effectiveness and cost considerations

Methicillin-resistant Staphylococcus aureus (MRSA) isolates is a serious public health problem whose ever-increasing rate is commensurate with the pressure it is exerting on the healthcare system. At present, more than 20% of clinical S. aureus isolates in German hospitals are methicillin resistant. Strategies from low-prevalence countries show that this development is not necessarily inevitable. In the Scandinavian countries and the Netherlands, thanks to a rigorous prevention programme, MRSA prevalence has been kept at an acceptably low level (<1–3%). Central to these ‘search and destroy’ control strategies is an admission screening using several MRSA swabs taken from mucocutaneous colonisation sites of high-risk patients (‘MRSA surveillance’)

Justification of method of calculation of stress-strain state of hoisting rubber-cable rope considering influence of cable base breakages and multiple factors

Розробка та обґрунтування методу аналітичного визначення напружено-деформованого стану плоского гумотросового каната шахтної підйомної машини з урахуванням впливу комплексу зовнішніх чинників, включно таких, як технічний стан машини та напрямних посудини та втрати тягової спроможності каната, зумовленою розривами суцільності тросів. Методика дослідження полягає в розробці математичної моделі напружено-деформованого стану гумотросового каната шахтної підйомної машини з урахуванням впливу комплексу чинників і розривів тросової основи та побудові аналітичних рішень для різних граничних умов деформування каната.Development and justification of a method of analytical determination of a stress-strain state of a flat rubber-cable rope of a mine hoisting machine considering the influence of multiple external factors, including such as technical condition of a machine and vessel guides, and loss of rope tractive capacity caused by cable breakages. Methodology of research is to develop a mathematical model of a stress-strain state of a rubber-cable rope of a mine hoisting machine considering the influence of multiple factors and cable base breakages and construction of analytical solutions for different boundary conditions of rope deformatio