Three participatory geographers: reflections on positionality and working with participants in researching religions, spiritualities, and faith

This paper advances the geographies of religion, spirituality and faith's limited attention to positionality by discussing the critical issues raised when using participatory approaches. Reflecting on three cases of participatory research, we foreground the dynamics of being a researcher with faith when working with participants from faith communities. Advocating participatory approaches as valuable methodologies that should be used more extensively to explore beliefs, faith practices, and social justice, we argue that greater attention needs to be given to the positionality of researchers undertaking this sort of research. Our cases raise three themes for discussion. First, the variety of ways in which faith positionalities influence how research is developed, conducted and concluded. Second, the intersections between our faith and other positionalities and how they shape our roles and relationships with research participants. Third, the fluid and multifaceted nature of faith positionalities and how they are changed, emphasized, and softened through the dynamics and entanglements of fieldwork. In doing so, we reflect on the complexities of being a researcher with faith, argue that faith positionality is a helpful dimension of their research rather than a limitation, and that all cultural, social and historical geographical researchers should reflect on their faith positionality

Optimum solids concentration in an agitated vessel

Particle suspension in high-concentration slurries has been studied using radial-, mixed-, and axial-flow impellers. Impeller power measurements in this study were linked to the mass of solids suspended in the agitation system rather than the suspension volume. This approach was based on the consideration that the rate of dissolution or reaction depends to a large extent on the exposed surface area or mass of solids and might not be affected by the suspension volume, once off-bottom suspension is achieved. It was found that the specific power, based on the mass of solids, can be minimized by operating the system at relatively higher solids concentrations in the range of 0.20-0.35 (v/v) for the solids, impeller types, and geometrical conditions used in this work. Overall, improved energy efficiency can be achieved by using higher-power-number impellers under unbaffled conditions over a range of solids concentrations. A case example is illustrated to demonstrate the benefits of adopting some of the optimization methods highlighted in this article

Clear model fluids for peculiar rheological properties of thickened digested sludge

Optimising flow processes in wastewater treatment plants requires that designers and operators take into account the flow properties of the sludge. Moreover, due to increasingly more stringent conditions on final disposal avenues such as landfill, composting, incineration etc., practitioners need to produce safer sludge in smaller quantities. Anaerobic digestion is a key treatment process for solids treatment and pathogen reduction. Due to the inherent opacity of sludge, it is impossible to visualise the mixing and flow patterns inside an anaerobic digester. Therefore, choosing an appropriate transparent model fluid which can mimic the rheological behaviour of sludge is imperative for visualisation of the hydrodynamic functioning of an anaerobic digester. Digested sludge is a complex material with time dependent non-Newtonian thixotropic characteristics. In steady state, it can be modelled by a basic power-law. However, for short-time processes the HerscheleBulkley model can be used to model liquid-like properties. The objective of this study was to identify transparent model fluids which will mimic the behaviour of real sludge. A comparison of three model fluids, Carboxymethyl Cellulose (CMC), Carbopol gel and Laponite clay revealed that these fluids could each model certain aspects of sludge behaviour. It is concluded that the rheological behaviour of sludge can be modelled using CMC in steady state flow at high shear rates, Carbopol gel for short-time flow processes and Laponite clay suspension where time dependence is dominant

(In Press) Rheological characterisation of municipal sludge: A review

Sustainable sludge management is becoming a major issue for wastewater treatment plants due to increasing urban populations and tightening environmental regulations for conventional sludge disposal methods. To address this problem, a good understanding of sludge behaviour is vital to improve and optimize the current state of wastewater treatment operations. This paper provides a review of the recent experimental works in order for researchers to be able to develop a reliable characterization technique for measuring the important properties of sludge such as viscosity, yield stress, thixotropy, and viscoelasticity and to better understand the impact of solids concentrations, temperature, and water content on these properties. In this context, choosing the appropriate rheological model and rheometer is also important

The influence of ultrasonic surface rolling on the fatigue and wear properties of 23-8N engine valve steel

An ultrasonic surface rolling (USR) technique was employed for the first time as a method to enhance the fatigue and wear resistance of 33Cr23Ni8Mn3N (23–8N) austenitic engine valve steel. The microstructure of the modified layer on the material surface was characterised by scanning electron microscopy (SEM) coupled with electron back scatter diffraction (EBSD) and transmission electron microscope (TEM) methods. Nanoscale lamellar grains were discovered on the top surface of the treated material, and an increase of compressive residual stress and microhardness of the surface material observed. A comparative fretting wear test and a rotating bending fatigue test were performed out to verify the surface enhancement effect. Fractured and worn faces of specimens were evaluated through utilizing SEM and energy–dispersive spectroscopy (EDS). Compared to the untreated material, the coefficient of friction of USR treated material was significantly reduced, and the wear resistance was improved. The fatigue strength of a specimen treated at 25 °C was increased from 528 MPa to 730 MPa (38.3 %). At 650 °C, the fatigue strength increased from 345 MPa to 400 MPa (15.9 %). The fatigue resistance extension and wear resistance improvement of treated specimen can be attributed to a combination of beneficial compressive residual stress, work hardening, and the modified microstructure with fine-grains in the surface layer, and thus demonstrates the validity of this novel technique

The role of private rental brokerage in housing outcomes for vulnerable Australians: Final report

This Final Report outlines the findings of research investigating the role of private rental brokerage in supporting housing outcomes for vulnerable households in the private rental market. In the last two decades the private rental market has become increasingly important in providing homes for Australians. It has also become increasingly competitive, particularly at the lower-end, where supply has fallen significantly behind demand. Given the lack of affordable ownership options in many local housing markets, and the contraction of public housing, many households with low or moderate means must now look to the private rental sector for their housing over the longer term. Government policy has encouraged renters who would otherwise be eligible for social housing to move into the private rental market. This tenure shift has been supported by the provision of several assistance measures for private renters. Those best known and understood are Commonwealth Rent Assistance (CRA) and state and territory Private Rent Assistance (PRA) programs, which provide bond and rent loans to eligible people. Two other elements also exist alongside the best known private rental supports: the National Rental Affordability Scheme (NRAS) (although as the planned further expansion of this scheme was halted by the newly elected Abbott Government in budget 2014/15 thereby limiting its future potential as a supply-side private rental assistance measure) and private rental brokerage. This report is concerned specifically with private rental brokerage; a previously underresearched measure among private rental supports nationally. Conceptually, we describe private rental brokerage as the 'third pillar' of supports nationally, sitting alongside the much larger CRA measure and, as the research findings reported here note, reinforcing the reach and impact of PRA.Selina Tually, Michele Slatter, Debbie Faulkner and Susan Oakley for the Australian Housing and Urban Research Institute at The University of Adelaid

Congenital Nephrotic Syndrome in IL7Rα-SCID: A Rare Feature of Maternofetal Graft-Versus-Host Disease

info:eu-repo/semantics/publishedVersio

Monomeric PcrA helicase processively unwinds plasmid lengths of DNA in the presence of the initiator protein RepD

The helicase PcrA unwinds DNA during asymmetric replication of plasmids, acting with an initiator protein, in our case RepD. Detailed kinetics of PcrA activity were measured using bulk solution and a single-molecule imaging technique to investigate the oligomeric state of the active helicase complex, its processivity and the mechanism of unwinding. By tethering either DNA or PcrA to a microscope coverslip surface, unwinding of both linear and natural circular plasmid DNA by PcrA/RepD was followed in real-time using total internal reflection fluorescence microscopy. Visualization was achieved using a fluorescent single-stranded DNA-binding protein. The single-molecule data show that PcrA, in combination with RepD, can unwind plasmid lengths of DNA in a single run, and that PcrA is active as a monomer. Although the average rate of unwinding was similar in single-molecule and bulk solution assays, the single-molecule experiments revealed a wide distribution of unwinding speeds by different molecules. The average rate of unwinding was several-fold slower than the PcrA translocation rate on single-stranded DNA, suggesting that DNA unwinding may proceed via a partially passive mechanism. However, the fastest dsDNA unwinding rates measured in the single-molecule unwinding assays approached the PcrA translocation speed measured on ssDNA