Stochastic signal analysis of thermally induced vestibular electronystagmograms

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Optimisation of the T-square sampling method to estimate population sizes.

Population size and density estimates are needed to plan resource requirements and plan health related interventions. Sampling frames are not always available necessitating surveys using non-standard household sampling methods. These surveys are time-consuming, difficult to validate, and their implementation could be optimised. Here, we discuss an example of an optimisation procedure for rapid population estimation using T-Square sampling which has been used recently to estimate population sizes in emergencies. A two-stage process was proposed to optimise the T-Square method wherein the first stage optimises the sample size and the second stage optimises the pathway connecting the sampling points. The proposed procedure yields an optimal solution if the distribution of households is described by a spatially homogeneous Poisson process and can be sub-optimal otherwise. This research provides the first step in exploring how optimisation techniques could be applied to survey designs thereby providing more timely and accurate information for planning interventions

Health effects of home energy efficiency interventions in England: a modelling study

Objective: To assess potential public health impacts of changes to indoor air quality and temperature due to energy efficiency retrofits in English dwellings to meet 2030 carbon reduction targets. Design: Health impact modelling study. Setting: England. Participants: English household population. Intervention: Three retrofit scenarios were modelled: (1) fabric and ventilation retrofits installed assuming building regulations are met. (2) As with scenario (1) but with additional ventilation for homes at risk of poor ventilation. (3) As with scenario (1) but with no additional ventilation to illustrate the potential risk of weak regulations and non-compliance. Main Outcome: Primary outcomes were changes in quality adjusted life years (QALYs) over 50 years from cardiorespiratory diseases, lung cancer, asthma and common mental disorders due to changes in indoor air pollutants, including: second-hand tobacco smoke, PM2.5 from indoor and outdoor sources, radon, mould, and indoor winter temperatures. Results: The modelling study estimates showed that scenario (1) resulted in positive effects on net mortality and morbidity of 2,241 (95% credible intervals (CI) 2,085 to 2,397) QALYs per 10,000 persons over 50 years due to improved temperatures and reduced exposure to indoor pollutants, despite an increase in exposure to outdoor–generated PM2.5. Scenario (2) resulted in a negative impact of -728 (95% CI -864 to -592) QALYs per 10,000 persons over 50 years due to an overall increase in indoor pollutant exposures. Scenario (3) resulted in -539 (95% CI -678 to -399) QALYs per 10,000 persons over 50 years due to an increase in indoor exposures despite targeting. Conclusions: If properly implemented alongside ventilation, energy efficiency retrofits in housing can improve health by reducing exposure to cold and air pollutants. Maximising the health benefits requires careful understanding of the balance of changes in pollutant exposures, highlighting the importance of ventilation to mitigate the risk of poor indoor air quality

New Climate Economics: Methodological Choices and Recommendations

Projections of future impacts, benefits and costs of climate mitigation and adaptation policies are based on both detailed empirical research, and modelling choices and assumptions that frame the analysis. For instance, assumptions about the expected growth of population and incomes drive the projections of greenhouse gas emissions. Assumptions about the pace and nature of innovation, the economy-environment-society interactions and the relative value of future versus current resources affect the estimates of the long-run benefits or costs of climate policies. Assumptions about future population health in the business-as-usual scenario affect the estimates of the health benefits or harms of climate change mitigation and adaptation policies. Further, estimates and assumptions regarding climate variability affect the benefits of adaptation measures to tackle potential increases in climate-related extreme events. Also, methodological choices about the treatment of disparate, incommensurable impacts are often decisive for policy decisions. This document presents a series of what we refer to as critical issues for climate mitigation and adaptation policy analysis, involving overarching choices that affect multiple areas of expert analysis, and in particular the socio-economic assessments of climate policies. The following pages identify key issues for a comprehensive and realistic economic analysis of climate policies, present a few major options for answering those issues, and recommend a preferred course of action or option for analysts to consider (akin to what some refer to as "new economic thinking"). The issue of risk and uncertainty has been addressed in a separate supporting guidance document, due to its overriding importance and specific inter-disciplinary profile (available on the website of the MCA4climate initiative: www.mca4climate.info). In addition, some practical implementation aspects of the issues discussed below have been provided in Annex 1 at the end of this document. Some of the topics addressed here may be more amenable to qualitative than to quantitative analysis; potential examples include the valuation of non-market "goods" such as human health and environmental protection, and the goal of intergenerational equity. It is nonetheless important to understand the implications of both quantitative and qualitative approaches to these issues, since both approaches are often raised in the discussion of climate policy. The guiding principles underpinning the overall MCA4climate approach

Assessing the performance of Internal Wall Insulation considering transient conditions

Recent research suggests that every insulation material undergoes failure in varying degrees of severity. Based on data derived from specified mould risk failure criteria, this study developed a novel equation to quantify the performance of insulation materials/systems following such transient conditions. Transient conditions performance (TCP) was quantified using the period after exceeding the risk criteria, the duration of exceedance and recovery time. The current formulation does not readily distinguish between materials based on their ability to cope with transient conditions. Further research was initiated to incorporate more diverse variables with which to expand the specificity of the TCP quantification

Linking complexity economics and systems thinking, with illustrative discussions of urban sustainability

The expanding research of complexity economics has been signalling its preference for a formal quantitative investigation of diverse interactions between heterogeneous agents at the lower, micro-level resulting in emergent, realistic socioeconomic dynamics at the higher, macro-level. However, there is scarcity in research that explicitly links complexity perspectives in economics with the systems thinking literature, despite these being highly compatible, with strong connections and common historical traces. We aim to address this gap by exploring commonalities and differences between the two bodies of knowledge, seen particularly through an economics lens. We argue for a hybrid approach, in that agent-based complexity perspectives in economics could more closely connect to two main systems thinking attributes: a macroscopic approach to analytically capturing the complex dynamics of systems, and an inter-subjective interpretivist dimension, when investigating complex social-economic order. Illustrative discussions of city sustainability are provided, with an emphasis on decarbonisation and residential energy demand aspects

Assessing fungal risk criteria via simulated scenarios to address disparity between method and outcomes

Internal wall insulation is one of the most promising methods of improving the energy efficiency of buildings while maintaining their original facades and construction. However, porous materials or poor construction quality can allow moisture ingress, creating favourable conditions for mould development within building fabric. Currently, there is no established guidance on moisture criteria in the construction industry for the assessment of interstitial mould growth. Some studies have considered relative humidity (RH) criteria that account for the duration of exposure but potentially overestimate risk at interfaces. This study implemented more specific RH criteria, based not only on the duration of exposure but also on temperature and substrate material. Results demonstrated a dramatic decrease in predicted mould risk, with minimal risk to health or structural integrity, in comparison to the present more stringent standards

Home Energy Efficiency and Subjective Health in Greater London

The UK has introduced legislation that requires net-zero greenhouse gas emissions to be achieved by 2050. Improving the energy efficiency of homes is a key objective to help reach this target, and the UK government's Clean Growth Strategy aims to get many homes up to an Energy Performance Certificate (EPC) Band of C by 2035. The relationship between home energy-efficiency and occupant health and wellbeing remains an area of ongoing research. This paper explores the nexus between home energy efficiency, energy consumption and self-reported health-an indicator of the general health and wellbeing of the population. We focus on Greater London through secondary data analysis. Energy-efficiency ratings and air infiltration rates of dwellings, derived from EPCs, were aggregated and matched to local area self-reported health and energy consumption data obtained from the Greater London Authority's (GLA) Lower Layer Super Output Area (LSOA) Atlas database. Our regression model indicates that improving the energy efficiency (SAP) rating by 10 points for a typical home may reduce household gas consumption by around 7% (95% CIs: 2%, 14%). Beta regression finds a positive, but not statistically significant association between median SAP rating and the proportion of the population reporting 'good or very good' health when considering all Greater London LSOAs (z score = 0.60, p value = 0.55). A statistically significant positive association is observed however when repeating the analysis for the lowest income quartile LSOAs (z score = 2.03, p value = 0.04). This indicates that the least well-off may benefit most from home energy efficiency programs. A statistically significant positive association is also observed for the relationship between self-reported health and air infiltration rates (z score = 2.62, p value = 0.01). The findings support existing evidence for the predominantly naturally ventilated UK housing stock, suggesting that home energy efficiency measures provide a co-benefit for occupant health provided that adequate air exchange is maintained

Modelling uniformly porous façades to predict dwelling infiltration rates

It is important to limit dwelling infiltration to reduce energy demand and help meet national climate change commitments while concurrently providing sufficient ventilation to deliver adequate indoor air quality. DOMVENT3D is a model of infiltration and exfiltration that assumes a linear pressure distribution over any number of uniformly porous facades and integrates the airflow rate in the vertical plane to predict the theoretically correct airflow rate through them. DOMVENT3D is a new development of an existing two-dimensional model of infiltration that provides more opportunities for investigating a greater number of dwellings than was previously possible. Initial testing suggests that DOMVENT3D is mathematically robust and is suitable for modelling a wide variety of dwelling types and geometries to assist engineers and policy makers. Practical application: The modern building services engineer may be required to model airflow networks in a building to balance the conflicting needs of energy consumption reduction and occupant health. Limiting exfiltration is one method of reducing heat losses from a building and so there is a need to model it accurately. This article presents a new model of infiltration and exfiltration through a uniformly porous facade that can be incorporated within advanced complex airflow network tools or applied using a simple spreadsheet