SUMMARY The T cell receptor (TCR) and CD8 bind peptide-major histocompatibility complex (pMHC) glycoproteins to initiate adaptive immune responses, yet the trimolecular binding kinetics at the T cell membrane is unknown. Using a micropipette adhesion frequency assay, we show that this kinetic has two stages. The first consists of TCR-dominant binding to agonist pMHC. This triggers a second stage consisting of a step increase in adhesion following a one second delay. The second-stage binding requires Src family kinase activity to initiate CD8 binding to the same pMHC engaged by the TCR. This induced-trimeric-cooperative interaction enhances adhesion synergistically to favor potent ligands, which further amplifies discrimination. Our data reveal a TCR-CD8 positive feedback loop involved in initial signaling steps that is sensitive to a single pMHC, is rapid, reversible, synergistic, and peptide-discriminative.

A novel mixed method smart metering approach to reconciling differences between perceived and actual residential end use water consumption.

On-site wastewater treatment and dispersal systems (OWTS) are used in non-sewered populated areas in Australia to treat and dispose of household wastewater. The most common OWTS in Australia is the septic tank–soil absorption system (SAS)—which relies on the soil to treat and disperse effluent. The mechanisms governing purification and hydraulic performance of a SAS are complex and have been shown to be highly influenced by the biological zone (biomat) which develops on the soil surface within the trench or bed. Studies suggest that removal mechanisms in the biomat zone, primarily adsorption and filtering, are important processes in the overall purification abilities of a SAS. There is growing concern that poorly functioning OWTS are impacting upon the environment, although to date, only a few investigations have been able to demonstrate pollution of waterways by on-site systems. In this paper we review some key hydrological and biogeochemical mechanisms in SAS, and the processes leading to hydraulic failure. The nutrient and pathogen removal efficiencies in soil absorption systems are also reviewed, and a critical discussion of the evidence of failure and environmental and public health impacts arising from SAS operation is presented. Future research areas identified from the review include the interactions between hydraulic and treatment mechanisms, and the biomat and sub-biomat zone gas composition and its role in effluent treatment.

COVID-19 is a wicked problem for policy makers internationally as the complexity of the pandemic transcends health, environment, social and economic boundaries. Many countries are focusing on two key responses, namely virus containment and financial measures, but fail to recognise other aspects. The systems approach, however, enables policy makers to design the most effective strategies and reduce the unintended consequences. To achieve fundamental change, it is imperative to firstly identify the “right” interventions (leverage points) and implement additional measures to reduce negative consequences. To do so, a preliminary causal loop diagram of the COVID-19 pandemic was designed to explore its influence on socio-economic systems. In order to transcend the “wait and see” approach, and create an adaptive and resilient system, governments need to consider “deep” leverage points that can be realistically maintained over the long-term and cause a fundamental change, rather than focusing on “shallow” leverage points that are relatively easy to implement but do not result in significant systemic change.

The purpose of this study was to explore the predominant determinants of shower end use consumption and to find an overarching research design for building a residential end use demand forecasting model using aligned socio-demographic and natural science data sets collected from 200 households fitted with smart meters in Southeast Queensland, Australia. ANOVA as well as multiple regression analysis statistical techniques were utilised to reveal the determinants (e.g. household makeup, shower fixture efficiency, income, education, etc.) of household shower consumption. Results of a series of one-way independent ANOVA extended into linear multiple regression models revealed that females, children in general and teenagers in particular, and the showerhead efficiency level were statistically significant determinants of shower end use consumption. Eight-way independent factorial ANOVA extended into a three-tier hierarchical linear multiple regression model, was used to create a shower end use forecasting model, and indicated that household size and makeup, as well as the showerhead efficiency rating, are the most significant predictors of shower usage. The generated multiple regression model was deemed reliable, explaining 90.2% of the variation in household shower end use consumption. The paper concludes with a discussion on the significant shower end use determinants and how this statistical approach will be followed to predict other residential end uses, and overall household consumption. Moreover, the implications of the research to urban water conservation strategies and policy design, is discussed, along with future research directions.

Bottom-up urban water demand forecasting based on empirical data for individual water end uses or micro-components (e.g., toilet, shower, etc.) for different households of varying characteristics is undoubtedly superior to top-down estimates originating from bulk water metres that are currently performed. Residential water end-use studies partially enabled by modern smart metering technologies such as those used in the South East Queensland Residential End Use Study (SEQREUS) provide the opportunity to align disaggregated water end-use demand for households with an extensive database covering household demographic, socioeconomic and water appliance stock efficiency information. Artificial Neural Networks (ANNs) provide the ideal technique for aligning these databases to extract the key determinants for each water end-use category, with the view to building a residential water end-use demand forecasting model. Three conventional ANNs were used: two feed-forward back propagation networks and one radial basis function network. A sigmoid activation hidden layer and linear activation output layer produced the most accurate forecasting models. The end-use forecasting models had R 2 values of 0.33, 0.37, 0.60, 0.57, 0.57, 0.21 and 0.41 for toilet, tap, shower, clothes washer, dishwasher, bath and total internal demand, respectively. All of the forecasting models except the bath demand were able to reproduce the means and medians of the frequency distributions of the training and validation sets. This study concludes with an application of the developed forecasting model for predicting the water savings derived from a citywide implementation of a residential water appliance retrofit program (i.e., retrofitting with efficient toilets, clothes washers and shower heads).

Rainwater Harvesting Systems (RHS) are increasingly used in buildings to mitigate water shortage and rising prices of centralised water supply. Notwithstanding the benefits of RHS, they may also promote adverse impacts mainly related to the high consumption of energy. In this context, energy intensity (i.e. unit of energy per unit of water) is a crucial parameter for assessing the environmental feasibility of different RHS. However, only recently has attention been drawn to the connection between water and energy consumption, which has been prompted by the increasing importance of water security, energy efficiency and economic feasibility. This connection, known as the water-energy nexus, has been increasingly acknowledged as a key principal for water planning. The objective of this study is twofold: (i) to review the energy intensity data reported for RHS; and (ii) to outline strategies to enhance the energy performance of RHS in buildings. For the reviewed literature, the median energy intensity of theoretical studies (0.20 kWh/m³) was considerably lower than that described in empirical studies (1.40 kWh/m³). This implies that theoretical assessments of energy intensity may not sufficiently consider the energy used for pump start-ups and standby mode, as well as the true motor and pump energy efficiency. However, to some extent, this difference may also represent the amount of energy that can be reduced by optimising RHS design and operation. When comparing RHS to conventional town water supply systems, the reviewed empirical studies showed that RHS tend to be three times more energy intensive, although optimised RHS can have more comparable values.Ultimately, it is predominately the local characteristics, such as rainwater demand, building type (single-storey or multi-storey), RHS sub-systems design, potable water plumbing system design, town water energy intensity, among other factors that will determine whether or not the environmental and economic performances of RHS are acceptable.

The role of 'smart metering' in demand management, customer service, labor optimization, and operational efficiency is becoming increasingly recognized by Australian water utilities. The objectives of this paper are to provide a summary of the 2013 and 2014 surveys and in-depth interviews that were aimed at gauging the penetration of smart metering (SM) and intelligent water network (IWN) projects in Australian and New Zealand water utilities and to identify outputs and challenges faced subsequent to their implementation.