Every year, one out of three adults over the age of 65 falls, and about 30% of the falls result in moderate to severe injuries. The high rate of fall-related hospitalizations and the fact that falls are a major source of morbidity and mortality in older adults have motivated extensive interdisciplinary clinical and engineering research with a focus on fall prevention. This research is aimed at developing a medical Cyber Physical System (CPS) composed of a human supervised mobile robot and ambient intelligence sensors to provide continuous evaluation of environmental risks in the home. As a preventive measure to avoid falls, we propose use of mobile robots to detect possible fall risks inside a house. As a step-up to that, we also define a control framework for intelligent, networked mobile robots to semi-autonomously perform assistive and preventive tasks. This framework is integrated in a smart home that provides monitoring and control capabilities of environmental conditions such as objects blocking pathways or uneven surfaces. The main outcome of this work is the realization of this system at Worcester Polytechnic Institute's (WPI) @Home testbed.

Oestrogenic chemicals have become increasingly associated with health effects in wildlife populations and humans. Transgenic animal models have been developed to understand the mechanisms by which these oestrogenic chemicals alter hormonal signalling pathways and how these alterations can lead to chronic health effects. The use of highly informative transgenic animal models will also result in better use and potential reduction of intact animals used in animal testing in line with the principles of the 3Rs. In this thesis work, two novel oestrogen responsive transgenic zebrafish models have been generated to investigate the effects of oestrogenic chemicals, identify their tissue targets and better understand the temporal dynamics of these responses. Both models express the pigment-free ‘Casper’ (a mutant line lacking skin pigment) phenotype, which facilitate identification of responding target tissues in the whole fish in all fish life stages (embryos to adults). The oestrogen response element green fluorescent (ERE-GFP)-Casper model was generated by crossing an established ERE-GFP line with the skin pigment free Casper line. The model generated is highly sensitive to oestrogenic chemicals, detecting responses to environmentally relevant concentrations of EE2, bisphenol A (BPA), genistein and nonylphenol. Use of the ERE-GFP- Casper model shows chemical type and concentration dependence for green fluorescent protein (GFP) induction and both spatial and temporal responses for different environmental oestrogens tested. A semi-automated (ArrayScan) imaging and image analysis system was also developed to quantify whole body fluorescence responses for a range of different oestrogenic chemicals in the new transgenic zebrafish model. The zebrafish model developed provides a sensitive and highly integrative system for identifying oestrogenic chemicals, their target tissues and effect concentrations for exposures in real time and across different life stages. It thus has application for chemical screening to better direct health effects analysis of environmental oestrogens and for investigating the functional roles of oestrogens in vertebrates. The second model generated was an ERE-Kaede-Casper line developed via crossing of the ERE-GFP-Casper line and a UAS-Kaede line and screening subsequent generations for a desired genotype and homozygous expression of the transgenes. Kaede is a photoconvertible fluorescent protein that initially fluoresces green in colour and can be permanently converted to red fluorescence upon short exposure to UV light. The model has a silenced skin pigmentation and high sensitivity to oestrogenic chemicals comparable with the previously developed ERE-GFP-Casper model. Use of this model has identified windows of tissue-specific sensitivity to ethinyloestradiol (EE2) for exposure during early-life (0-48hpf) and illustrated that exposure to oestrogen (EE2) during early life (0-48hpf) can enhance responsiveness (sensitivity) to different environmental oestrogens (EE2, genistein and bisphenol A) for subsequent exposures during development. These findings illustrate the importance of oestrogen exposure history in effects assessments and they have wider implications for the possible adverse effects associated with oestrogen exposure.