Understanding thermal comfort and wellbeing of older South Australians using occupant-centric models

The proportion of older people (i.e., those aged 65 or over) in the world’s population is increasing due to historically low fertility rates combined with increased life expectancy. In order to respond to these demographic trends, a growing body of policy and research over the last decades has accepted that ageing-in-place is most beneficial in the interests of older people’s independence, health and wellbeing, as well as to reduce the economic burden on governments and society for the provision of aged care facilities. While there are several guidelines that provide information about designing dwellings to suit ageing-in-place, information to aid older people’s thermal comfort and related wellbeing is not always considered. This thesis addresses the current knowledge on thermal comfort of older people in order to provide environments that meet their individual requirements and help improve their overall wellbeing. Traditionally, thermal comfort standards adopt aggregate modelling approaches as the bases on which to establish the requirements for human occupancy in the built environment. Aggregate models explain thermal comfort at a population level, which can result in limitations in real scenarios as individual thermal perceptions can vary significantly. In recent years, a growing number of studies have been conducted to address these limitations by developing ‘personal comfort models’. Instead of an average response from a large population, personalised models predict individuals’ thermal comfort by using a single person’s direct feedback. Nonetheless, up until the research presented in this thesis, studies on personal comfort models have focused on younger adults, generally in office environments. This presents a critical research gap because intergroup heterogeneity in personal capabilities and needs tends to be greater among older people, causing the use of aggregate models for older adults to result in even more frequent exposure to unacceptable thermal environments. These, in turn, can interact with multiple comorbidities, leading to adverse health outcomes and possibly premature institutional care. Thus, personalising models hold the promise of a more accurate way to predict older people’s thermal comfort and to manage their thermal environments better. Considering the issues and opportunity presented above, the goal of this research is to advance the current knowledge on the use of personal thermal comfort models by focusing on older people in their home environments. The research aims to achieve this goal by: (1) reviewing the present understandings of personal comfort models, (2) investigating older people’s’ thermal environment, behaviours and preferences; (3) developing personal comfort models for older people and comparing the results with the predictions by established aggregate models; and (4) investigating the application of personal comfort models in managing the thermal environment of older people. Two indoor environmental monitoring field studies and related point-in-time thermal comfort surveys were conducted to collect datasets for the analyses. The first dataset was collected from 71 older adults in 57 households located in South Australia across 9 months. This was followed by the application of deep learning (i.e., a class of machine learning) to develop personal comfort models for 28 out of these 71 participants using different combinations of the collected series of indoor environmental measurements, along with behavioural and health/wellbeing survey answers. The second dataset was collected during shorter 2-week periods involving 11 of the original 71 participants, during which, in addition to measuring the indoor environmental parameters and collecting behavioural and health/wellbeing survey answers, the participants’ hand skin temperatures were measured. The development of personal models for 4 of these participants was then conducted, including skin temperatures as an additional modelling input. Several performance indicators, including average accuracy, Cohen’s Kappa Coefficient and Area Under the Receiver Operating Characteristic Curve (AUC) were employed to assess the skill of the developed individual models. All models’ performance indicators were then compared with a ‘version’ of the Predicted Mean Vote (PMV) model, termed, in this thesis, the PMVc. The results showed that the 28 personal thermal comfort models for older adults that used environmental, behavioural and health/wellbeing perception as input variables presented an average accuracy of 74%, an average Cohen’s Kappa Coefficient of 61% and an average (AUC) of 0.83. This represented a significant improvement in predictive performance when compared with the generalised PMVc model, which presented an average accuracy of 50%, an average Cohen’s Kappa Coefficient of 24%, and an average AUC of 0.62. Similarly, the exploration with the 4 personal comfort models adding skin temperature measurements to the abovementioned input variables, and excluding health/wellbeing perception − which yielded slightly lower performance when included −, resulted in an average accuracy of 67%, an average Cohen’s Kappa Coefficient of 50% and an average AUC of 0.77. This also represented a superior predictive performance of the individualised models when compared with the PMVc model. In order to investigate the applications of the personal comfort models in operation, two participants were selected as case studies and their respective personal models were tested for their ability to estimate personal heating and cooling temperature set points, using calibrated building performance simulation models. The simulated energy loads derived from the use of personal set points were compared with simulated energy loads using 21°C as the heating set point and 24°C as the cooling set point, which represented the common averaged set points used in building simulation studies. The results show that, using the personal set points, good agreement between the actual and simulated heating and cooling energy loads was achieved. When comparing the error ratios with the ones resulting from simulations assuming a 21°C set point for heating and a 24°C for cooling, the study also showed that the personal set points significantly outperformed these traditional assumptions. Finally, as a secondary application exploration, one selected participant’s personal model was converted to a smart phone Application (App) format to examine the opportunity to use the model as a web-based smart phone tool to aid designers and caregivers to manage the thermal environments of older people by considering individual requirements. This conversion also proved to be successful, allowing the automatic calculation of thermal preference for the selected participant, thereby demonstrating its potential to aid designers and caregivers. The novelty and therefore the contributions of this research lay in different areas. Whilst the literature on personal comfort models has focussed solely on younger adults in office environments, this research has explored a methodology for predicting thermal comfort of older people in their dwellings. Additionally, it has introduced health/wellbeing perception as a predictor of thermal preference – a variable often overlooked in architectural sciences and building engineering. Finally, the research indicates that, compared with aggregated models, personal models provide superior utility in predicting an individual’s preferred thermal environment, which therefore offers the potential for more accurate tools to design and improve older people’s living environments so that wellbeing is optimised, healthy ageing is fostered and autonomy while ageing is prolonged. The research recommends a range of topics for future investigation, such as the models’ misclassification costs and the integration among wearable sensors, predictors and actuators in the context of older people. In addition, the development of standard protocols necessary for the models’ deployment in real scenarios is prescribed. In conclusion, the research demonstrates that, as a concept, personal comfort models have the ability to absorb people’s diversity in the context of their environmental conditions, and may therefore represent an important step towards providing knowledge aimed at enhancing wellbeing and improving the overall resilience of the built environment.Thesis (Ph.D.) -- University of Adelaide, School of Architecture and Built Environment, 202

Built Environment and Frailty: Understanding the influence of neighbourhood on older people’s health

"A thesis submitted to the University of Adelaide and Nagoya University in fulfilment of the requirements for the joint degree of Doctor of Philosophy"Never in the history of the world have so many humans lived for so long, with over 11% of the world's current population being 60 years old and older. Australia and Japan are the countries in the Western Pacific region with the highest proportion of older people aged 65 years old and over, estimated to reach 18.3% and 31.2% respectively by 2030. This demographic transition represents a significant challenge for health and social care systems. In this context, a study of frailty is of particular interest as we move away from disease-oriented models of care to more patient-oriented integrated care, considering biological and non-biological causes of disease. Frailty is defined as a state of extreme vulnerability to intrinsic and extrinsic stressors leading to an increased risk of adverse outcomes, such as hospitalisation, institutionalisation and death. The risk of frailty increases with age, with worldwide prevalence varying from 4.0% to 59.1%, depending on which criteria used and clinical context. The role of place in older adults’ health is not a new concept but has only recently been recognised as important for the achievement of healthy ageing. Although there is some research suggesting that the neighbourhood built environment is associated with walking, physical activity and well-being in older adults, very little has been done to investigate the relationships between frailty, objective neighbourhood environment and individual perceptions of the neighbourhood environment. This research sought to understand relationships between these factors in two culturally different cities, Nagoya, Japan and Adelaide, Australia. The interdisciplinary nature of the research required the development of new methods and the conduct of quantitative and mixed-method projects. Firstly we (1) assessed the level of importance medical students assigned to the topic of frailty after taking a geriatric medical course, along with their self-perceived competence in the area of frailty diagnosis and care. Then, a range of projects were undertaken to investigate the associations between neighbourhood environment and frailty: (2) a feasibility study of the research tools; (3) a mixed-method study investigating older adults’ experiences and perceptions of the public space of a hospital; (4) the development of a frailty index for the analysis of (5) the association between frailty and neighbourhood perceptions in older adults from Nagoya and (6), with similar methodology, investigation of the same associations in older adults from Adelaide, with adjustment for the objective environment. The initial feasibility study (2) identified successful recruiting strategies for frail older adults, as well as issues that needed to be addressed to improve execution and acceptance by older adults. The mixed-method study (3) identified aspects of the built environment that could be directly associated with older adults’ intrinsic capacity and elements that were facilitators or barriers to the use of the built space. Several themes were identified as associated with older adults’ experiences as outpatients, such as lighting, noise, temperature, design, seating, wayfinding and access/transportation. In the Nagoya Longitudinal Study for Healthy Elderly, using the frailty index (4), we identified the prevalence of frail and pre-frail older adults in the sample, and age, polypharmacy, physical activity, walking speed and weight circumference were significantly associated with being frail and pre-frail. Using this frailty index, the cross-sectional analysis of associations between frailty and neighbourhood environment in Nagoya (5) revealed that increased frailty was independently associated with worse perceptions of neighbourhood environment. There were inverse linear associations between the frailty index and perceptions of the neighbourhood environment, and higher frailty was associated with poorer perceptions of land use mix diversity, land use mix access, street connectivity, walking infrastructure, aesthetics, and crime safety. In Adelaide (6), with the inclusion of an objective record of the environmental characteristics of place, the neighbourhood environment variables retained a significant association with frailty, and specific associations were found between worse land use mix and accessibility and worse crime safety and frailty and pre-frailty. Finally, fifth-year medical students’ perceived competence and the level of importance assigned to assessing, diagnosing and managing frailty significantly improved after a geriatric medical course in the University of Adelaide (1). Increasing medical students’ awareness of frailty topic and attitudes towards ageing will help shape future health professionals in the better care of older adults in Australia. Frailty is a common and prevalent condition in older adults from Australia and Japan, and several modifiable risk factors have been identified in relation to frailty, with the neighbourhood environment being one of them. Research from this doctoral thesis contributes to the understanding of the complex relationship between the neighbourhood environment and frailty in older adults, delivering insights that need to be taken into consideration when assessing the impact of community settings on frailty, as well as the impact of frailty on perceptions of the built environment of the community. Medical students perceived competence on the assessment and management of frailty can be improved through a geriatric medicine course and it is important given population ageing that geriatric medicine teaching programs are included in medical program curricula. Frailty was independently associated with worse neighbourhood environment perceptions in Nagoya and Adelaide. This influence might lead to worse physical and social activities in the neighbourhood which might be a cause of increased frailty risk in the studied groups. In conclusion, considering the effects of the neighbourhood environment on older adults’ health is an important public health and therapeutic strategy to help manage and prevent frailty in the community.Thesis (Ph.D.) -- University of Adelaide, Adelaide Medical School, 202

Thermal personalities of older people in South Australia: A personas-based approach to develop thermal comfort guidelines

Published: 13 November 2020An important consideration for future age-friendly cities is that older people are able to live in housing appropriate for their needs. While thermal comfort in the home is vital for the health and well-being of older people, there are currently few guidelines about how to achieve this. This study is part of a research project that aims to improve the thermal environment of housing for older Australians by investigating the thermal comfort of older people living independently in South Australia and developing thermal comfort guidelines for people ageing-in-place. This paper describes the approach fundamental for developing the guidelines, using data from the study participants’ and the concept of personas to develop a number of discrete “thermal personalities”. Hierarchical Cluster Analysis (HCA) was implemented to analyse the features of research participants, resulting in six distinct clusters. Quantitative and qualitative data from earlier stages of the project were then used to develop the thermal personalities of each cluster. The thermal personalities represent different approaches to achieving thermal comfort, taking into account a wide range of factors including personal characteristics, ideas, beliefs and knowledge, house type, and location. Basing the guidelines on thermal personalities highlights the heterogeneity of older people and the context-dependent nature of thermal comfort in the home and will make the guidelines more user-friendly and useful.Helen Bennetts, Larissa Arakawa Martins, Joost van Hoof and Veronica Soebart

Horizontal patterns of water temperature and salinity in an estuarine tidal channel: Ria de Aveiro

This work presents results from two complementary and interconnected approaches to study water temperature and salinity patterns in an estuarine tidal channel. This channel is one of the four main branches of the Ria de Aveiro, a shallow lagoon located in the Northwest coast of the Iberian Peninsula. Longitudinal and cross-sectional fields of water temperature and salinity were determined by spatial interpolation of field measurements. A numerical model (Mohid) was used in a 2D depth-integrated mode in order to compute water temperature and salinity patterns. The main purpose of this work was to determine the horizontal patterns of water temperature and salinity in the study area, evaluating the effects of the main forcing factors. The field results were depth-integrated and compared to numerical model results. These results obtained using extreme tidal and river runoff forcing, are also presented. The field results reveal that, when the river flow is weak, the tidal intrusion is the main forcing mechanism, generating saline and thermal fronts which migrate with the neap/spring tidal cycle. When the river flow increases, the influence of the freshwater extends almost as far as the mouth of the lagoon and vertical stratification is established. Results of numerical modelling reveal that the implemented model reproduces quite well the observed horizontal patterns. The model was also used to study the hydrology of the study area under extreme forcing conditions. When the model is forced with a low river flow (1 m3 s−1) the results confirm that the hydrology is tidally dominated. When the model is forced with a high river flow (1,000 m3 s−1) the hydrology is dominated by freshwater, as would be expected in such an area

Pseudomonas aeruginosa amidase: Aggregation in recombinant Escherichia coli

The effect of cultivation parameters such as temperature incubation, IPTG induction and ethanol shock on the production of Pseudomonasaeruginosa amidase (E.C.3.5.1.4) in a recombinant Escherichia coli strain in LB ampicillin culture medium was investigated. The highest yield of solubleamidase, relatively to other proteins, was obtained in the condition at 37 degrees C using 0.40 mM IPTG to induce growth, with ethanol. Our results demonstrate the formation of insoluble aggregates containing amidase, which was biologically active, in all tested growth conditions. Addition of ethanol at 25 degrees C in the culture medium improved amidase yield, which quantitatively aggregated in a biologically active form and exhibited in all conditions an increased specific activity relatively to the soluble form of the enzyme. Non-denaturing solubilization of the aggregated amidase was successfully achieved using L-arginine. The aggregates obtained from conditions at 37 degrees C by Furier transform infrared spectroscopy (FTIR) analysis demonstrated a lower content of intermolecular interactions, which facilitated the solubilization step applying non-denaturing conditions. The higher interactions exhibited in aggregates obtained at suboptimal conditions compromised the solubilization yield. This work provides an approach for the characterization and solubilization of novel reported biologically active aggregates of this amidase

The Thermal Environment of Housing and Its Implications for the Health of Older People in South Australia: A Mixed-Methods Study

Published: 8 January 2022Older people are often over-represented in morbidity and mortality statistics associated with hot and cold weather, despite remaining mostly indoors. The study “Improving thermal environment of housing for older Australians” focused on assessing the relationships between the indoor environment, building characteristics, thermal comfort and perceived health/wellbeing of older South Australians over a study period that included the warmest summer on record. Our findings showed that indoor temperatures in some of the houses reached above 35 °C. With concerns about energy costs, occupants often use adaptive behaviours to achieve thermal comfort instead of using cooling (or heating), although feeling less satisfied with the thermal environment and perceiving health/wellbeing to worsen at above 28 °C (and below 15 °C). Symptoms experienced during hot weather included tiredness, shortness of breath, sleeplessness and dizziness, with coughs and colds, painful joints, shortness of breath and influenza experienced during cold weather. To express the influence of temperature and humidity on perceived health/wellbeing, a Temperature Humidity Health Index (THHI) was developed for this cohort. A health/wellbeing perception of “very good” is achieved between an 18.4 °C and 24.3 °C indoor operative temperature and a 55% relative humidity. The evidence from this research is used to inform guidelines about maintaining home environments to be conducive to the health/wellbeing of older people.Alana Hansen, TerenceWilliamson, Dino Pisaniello, Helen Bennetts, Joost van Hoof, Larissa Arakawa Martins, Renuka Visvanathan, Jian Zuo and Veronica Soebart

Air quality over Portugal in 2020

This works intends to evaluate the impacts of the national emission ceilings (NEC) reduction scenarios on the air quality in Portugal, verifying the fulfillment of the air quality thresholds for 2020. The air quality numerical modeling system WRF–EURAD was applied to this 2020 future scenario and results were compared to the present situation -year 2012. This modeling system was already evaluated for Portugal domain in previous studies, by comparison with measured air quality data, and showed reasonable skills for all the pollutants. This system was applied over the Continental domain of Portugal, using nesting approach, with a horizontal resolution of 5x5 km2, for both scenarios conditions (2012 and 2020) considering the respective emissions data and assuming the 2012 meteorological conditions. The results point towards an improvement of the air quality over Continental Portugal, in particular for particulate matter (in the urban areas of Lisbon and Porto) and SO2 (near specific industrial sources) but do not solve the non–compliance status regarding the O3 threshold value for protection of human health. These results strengthen the importance of including the NEC emission scenarios in the air quality national strategy, but additional mitigation actions need to be designed, with focus on ozone and its precursors, at local and regional scale

CARVÃO ATIVADO GRANULAR IMPREGNADO COM ZINCO PARA REMOÇÃO DE BACTÉRIAS DA ÁGUA PARA CONSUMO HUMANO

O carvão ativado granular impregnado com zinco (C/Zn) foi avaliado em relação à atividade antibacteriana para eliminação de micro-organismos na purificação de água para consumo humano. Os meios filtrantes produzidos a partir de C/Zn foram caracterizados através de técnicas instrumentais como análises de BET e difração de raios-X (DRX) para determinar a distribuição de poros e área superficial e as fases estruturais, respectivamente. Experimentos foram realizados em um sistema doméstico de purificação de água utilizando filtros com leito de carvão ativado granular sem impregnação e com impregnação de zinco nas concentrações de 1,0, 3,0, 5,0 e 10,0% (m/m). A atividade antibacteriana dos meios filtrantes foi avaliada em relação à eficiência de remoção de bactérias Escherichia coli da água. Foram preparadas soluções sintéticas com água deionizada contaminada artificialmente com uma concentração aproximada entre 1,0x105 a 9,0x106 UFC/100mL de Escherichia coli. Assim a eficiência bacteriológica dos meios filtrantes com C/Zn foi superior com o aumento da concentração de zinco impregnado no carvão ativado. O filtro com leito de carvão ativado impregnado com 10% de zinco apresentou a maior eficiência com remoção de Escherichia coli superior a 99% e melhorando a qualidade bacteriológica da água para consumo humano.AbstractGranular activated carbon impregnated with zinc (C/Zn) was evaluated for the antibacterial activity for elimination of micro-organisms in drinking water purification. The filter media produced from C/Zn were characterized by instrumental techniques such as the BET analyzes and x-ray diffraction (XRD) to determine the pore distribution and surface area and structural phases, respectively. Experiments were performed in a household water purification system using filters with granular activated carbon bed without impregnation and impregnation with zinc in concentrations of 1.0, 3.0, 5.0 and 10.0% (w/w). The antibacterial activity of the filter media was evaluated regarding to the removal efficiency of bacteria Escherichia coli of water. Synthetic solutions were prepared with deionized water contaminated artificially with an approximate concentration of 1.0 x105 to 9.0 x106 CFU/100mL of Escherichia coli. The efficiency bacteriological efficiency bacteriological of filter media with C/Zn was higher with increasing concentration of zinc impregnated on activated carbon.The filter bed of activated carbon impregnated with 10% of zinc showed the highest efficiency with removal of bacterial Escherichia coli higher than 98% and improving the bacteriological quality of drinking water

On the Chemistry, Toxicology and Genetics of the Cyanobacterial Toxins, Microcystin, Nodularin, Saxitoxin and Cylindrospermopsin

The cyanobacteria or “blue-green algae”, as they are commonly termed, comprise a diverse group of oxygenic photosynthetic bacteria that inhabit a wide range of aquatic and terrestrial environments, and display incredible morphological diversity. Many aquatic, bloom-forming species of cyanobacteria are capable of producing biologically active secondary metabolites, which are highly toxic to humans and other animals. From a toxicological viewpoint, the cyanotoxins span four major classes: the neurotoxins, hepatotoxins, cytotoxins, and dermatoxins (irritant toxins). However, structurally they are quite diverse. Over the past decade, the biosynthesis pathways of the four major cyanotoxins: microcystin, nodularin, saxitoxin and cylindrospermopsin, have been genetically and biochemically elucidated. This review provides an overview of these biosynthesis pathways and additionally summarizes the chemistry and toxicology of these remarkable secondary metabolites

Behavioral and Chemical Ecology of Marine Organisms with Respect to Tetrodotoxin

The behavioral and chemical ecology of marine organisms that possess tetrodotoxin (TTX) has not been comprehensively reviewed in one work to date. The evidence for TTX as an antipredator defense, as venom, as a sex pheromone, and as an attractant for TTX-sequestering organisms is discussed. Little is known about the adaptive value of TTX in microbial producers; thus, I focus on what is known about metazoans that are purported to accumulate TTX through diet or symbioses. Much of what has been proposed is inferred based on the anatomical distribution of TTX. Direct empirical tests of these hypotheses are absent in most cases