A low-cost system for seismocardiography-based cardiac triggering: A practical solution for cardiovascular magnetic resonance imaging at 3 tesla

This study describes a pilot clinical validation of a new low-cost system for the continuous monitoring of the human body's cardiorespiratory activities within the magnetic resonance examination area. This study primarily focuses on monitoring cardiac activity and the related cardiac triggering. The patented system tested by the authors is based on seismocardiography (SCG). The study was conducted on 18 subjects on a Siemens Prisma 3T MR scanner. Standard anatomical and diffusion sequences were used to test cardiac activity monitoring. A wide range of commonly used diagnostic sequences were used to test imaging of the heart by means of cardiac triggering. System functionality was verified against a commercially available electrocardiography (ECG) system. Monitoring of cardiac activity (detection of the R-R interval in ECG and the AO-AO interval in SCG) was objectively evaluated by determining the overall probability of correct detection (ACC), sensitivity (SE), positive predictive value (PPV), and harmonic mean between SE and PPV, i.e. F1. Imaging quality control using Cardiac Triggering was performed by subjective evaluation of images by the physicians. The study conducted clearly confirmed the functionality of the system in terms of continuous cardiac activity monitoring. In all 18 subjects, a mean PPV > 99% was achieved; F1 > 99 %; SE > 99 %; ACC > 98 %; 1.96 sigma < 3.5 bpm. Also, Cardiac Triggering functionality was confirmed by the physicians on the basis of analyzing cardiac images using the T1/T2 balanced echo sequences and the T1 flash sequence measured natively.Web of Science711862911860

Personalised Environmental Monitoring of Building Occupants: Integration of Scalable Technologies

Urbanised societies spend most of their time indoor. These are places to conduct habitual activities that impact across the life course and are generating discussions on the built environment and its interplay with health and wellbeing. To understand the effect buildings and their enclosed spaces have on people/occupants, there is a need to monitor Indoor Environmental Quality (IEQ) and occupant responses. State-of-the-art monitoring approaches exist, but they have limited utility outside of bespoke scenarios due to their limited pragmatism and large cost. Other emergent technologies exist but questions remain relating to e.g., validity. Other routine/traditional subjective approaches for evaluating building IEQ often negate to account for the experiences of individual occupants, adding to complications. This thesis explores current monitoring IEQ trends, uncovering the needs to make the individual the unit of analysis. Research undertaken explores contemporary needs and shifting trends to pragmatic approaches, localised sensors to provide richer data that could enable a better understanding of environmental and occupant changes. Quantitative measurement of the environmental conditions local to individuals are explored to understand whether spatial density in monitoring can 1) reinforce data pertaining to how building occupants experience indoor conditions and 2) provide additional context to current approaches for data capture, which traditionally focus on qualitative approaches. Through a series of original research this thesis broadly presents the design and development of a multi-modal IEQ monitoring device and a supporting methodological process for monitoring individuals. It identifies that low-cost multi-modal monitoring deployed longitudinally can add significant context to traditional qualitative approaches, with the individual as the unit of analysis. Findings from the thesis present a paradigm shift that could have practical implications for researchers and practitioners, changing the way building performance is assessed and the way its impact on health and wellbeing could be evaluated

Aerospace medicine and biology: A continuing bibliography with indexes, supplement 239, December 1982

This bibliography lists 318 reports, articles and other documents introduced into the NASA scientific and technical information system in November 1982