Traffic and nucleation events as main sources of ultrafine particles in high-insolation developed world cities

Road traffic emissions are often considered the main source of ultrafine particles (UFP, diameter smaller than 100 nm) in urban environments. However, recent studies worldwide have shown that - in high-insolation urban regions at least - new particle formation events can also contribute to UFP. In order to quantify such events we systematically studied three cities located in predominantly sunny environments: Barcelona (Spain), Madrid (Spain) and Brisbane (Australia). Three long term datasets (1-2 years) of fine and ultrafine particle number size distributions (measured by SMPS, Scanning Mobility Particle Sizer) were analysed. Compared to total particle number concentrations, aerosol size distributions offer far more information on the type, origin and atmospheric evolution of the particles. By applying k-Means clustering analysis, we categorized the collected aerosol size distributions in three main categories: “Traffic” (prevailing 44-63% of the time), “Nucleation” (14-19%) and “Background pollution and Specific cases” (7-22%). Measurements from Rome (Italy) and Los Angeles (California) were also included to complement the study. The daily variation of the average UFP concentrations for a typical nucleation day at each site revealed a similar pattern for all cities, with three distinct particle bursts. A morning and an evening spike reflected traffic rush hours, whereas a third one at midday showed nucleation events. The photochemically nucleated particles burst lasted 1-4 hours, reaching sizes of 30-40 nm. On average, the occurrence of particle size spectra dominated by nucleation events was 16% of the time, showing the importance of this process as a source of UFP in urban environments exposed to high solar radiation. On average, nucleation events lasting for 2 hours or more occurred on 55% of the days, this extending to >4hrs in 28% of the days, demonstrating that atmospheric conditions in urban environments are not favourable to the growth of photochemically nucleated particles. In summary, although traffic remains the main source of UFP in urban areas, in developed countries with high insolation urban nucleation events are also a main source of UFP. If traffic-related particle concentrations are reduced in the future, nucleation events will likely increase in urban areas, due to the reduced urban condensation sinks.

Economic analyses and policy implications for microalgae biofuels in Australia

The benefits of microalgae biofuels over first and second generation counterparts suggest it has potential as a major biofuel feedstock in Australia. However, the high costs of cultivation and processing has been a major drawback for investors and policymakers. This presentation outlines the economic potential for microalgae biofuels: firstly, through production of microalgae co-products (e.g feed and fertiliser); and secondly, deriving what consumers are willing to pay for microalgae biofuels based on external benefits. These findings will assist decision-makers in both private and public sectors and inform policy development with respect to microalgae as a feedstock for biofuels and other products. This study adds an economics perspective to the current technical literature which has been dominated by biochemical, engineering and financial valuation studies.

Direct electrochemical formation of nanostructured amorphous Co(OH)2 on gold electrodes with enhanced activity for the oxygen evolution reaction.

The oxides of cobalt have recently been shown to be highly effective electrocatalysts for the oxygen evolution reaction (OER) under alkaline conditions. In general species such as Co3O4 and CoOOH have been investigated that often require an elevated temperature step during their synthesis to create crystalline materials. In this work we investigate the rapid and direct electrochemical formation of amorphous nanostructured Co(OH)2 on gold electrodes under room temperture conditions which is a highly active precursor for the OER. During the OER some conversion to crystalline Co3O4 occurs at the surface, but the bulk of the material remains amorphous. It is found that the underlying gold electrode is crucial to the materials enhanced performance and provides higher current density than can be achieved using carbon, palladium or copper support electrodes. This catalyst exhibits excellent activity with a current density of 10 mA cm-2 at an overpotential of 360 mV with a high turnover frequency of 2.1 s-1 in 1 M NaOH. A Tafel slope of 56 mV dec-1 at low overpotentials and a slope of 122 mV dec-1 at high overpotentials is consistent with the dual barrier model for the electrocatalytic evolution of oxygen. Significantly, the catalyst maintains excellent activity for up to 24 hr of continuous operation and this approach offers a facile way to create a highly effective and stable material.

Spectral analysis of pair-correlation bandwidth: Application to cell biology images

Images from cell biology experiments often indicate the presence of cell clustering, which can provide insight into the mechanisms driving the collective cell behaviour. Pair-correlation functions provide quantitative information about the presence, or absence, of clustering in a spatial distribution of cells. This is because the pair-correlation function describes the ratio of the abundance of pairs of cells, separated by a particular distance, relative to a randomly distributed reference population. Pair-correlation functions are often presented as a kernel density estimate where the frequency of pairs of objects are grouped using a particular bandwidth (or bin width), Δ>0. The choice of bandwidth has a dramatic impact: choosing Δ too large produces a pair-correlation function that contains insufficient information, whereas choosing Δ too small produces a pair-correlation signal dominated by fluctuations. Presently, there is little guidance available regarding how to make an objective choice of Δ. We present a new technique to choose Δ by analysing the power spectrum of the discrete Fourier transform of the pair-correlation function. Using synthetic simulation data, we confirm that our approach allows us to objectively choose Δ such that the appropriately binned pair-correlation function captures known features in uniform and clustered synthetic images. We also apply our technique to images from two different cell biology assays. The first assay corresponds to an approximately uniform distribution of cells, while the second assay involves a time series of images of a cell population which forms aggregates over time. The appropriately binned pair-correlation function allows us to make quantitative inferences about the average aggregate size, as well as quantifying how the average aggregate size changes with time.

Is Habermas on Twitter? Social Media and the Public Sphere

Jürgen Habermas’s concept of the public sphere remains a major building block for our understanding of public communication and deliberation. Yet ‘the’ public sphere is a construct of its time, and the mass media-dominated environment which it describes has given way to a considerably more fragmented and complex system of distinct and diverse, yet interconnected and overlapping publics that represent different themes, topics, and approaches to mediated communication. This chapter argues that moving beyond the orthodox model of the public sphere to a more dynamic and complex conceptual framework provides the opportunity to more clearly recognise the varying forms that public communication can take, especially online. Unpacking the traditional public sphere into a series of public sphericules and micro-publics, none of which are mutually exclusive but which co-exist, intersecting and overlapping in multiple forms, is crucial for understanding the ongoing structural transformation of ‘the’ public sphere.

Transdisciplinary collaboration in wound care research

The highly complex disorder of chronic wounds is a significant problem. Information is often lacking, dynamically changing, or contradictory and thus acts to impede the progression of research and its translation into clinical care. Transdisciplinary collaboration may play an important role in chronic wound research, permitting key stakeholders with a single, central goal to take a unified approach towards addressing the problem. While transdisciplinary collaboration is not a new concept, its implementation within chronic wound research is relatively new. This is because the research area is still largely dominated by single-discipline researchers or by multiple disciplines working in isolation. Transdisciplinary research is a transcending approach, requiring a greater level of understanding between disciplines and may represent the next leap forward in wound care research. This approach necessitates a deeper understanding by all team members of the co-disciplines involved; where key stakeholders are better equipped to respond to dynamic changes and problems that arise in chronic wound research. In this paper, we illustrate what a transdisciplinary approach in wound care research may entail, with the ultimate goal of such an undertaking to improve understanding of the complexities of wound care, which could lead to potential benefits in wound management.

Customer inspired innovation with designer as innovation catalyst

This study explores the processes of introduction, implementation and integration of design-led innovation within a family owned company driven by engineering innovation in a sector dominated by product and process improvements. This paper is based on the outcomes of an investigation of a family manufacturing company in the METS sector over an 11-month period, where the researcher was embedded in the firm to deliver value to the company by using an action research approach. The design innovation catalyst used a design-led innovation process to capture customer insights that led to changes at the leadership, managerial and employee level of the organisation.

Using Lifespan developmental theory and methods as a viable alternative to the study of generational differences at work

I agree with Costanza and Finkelstein (2015) that it is futile to further invest in the study of generational differences in the work context due to a lack of appropriate theory and methods. The key problem with the generations concept is that splitting continuous variables such as age or time into a few discrete units involves arbitrary cutoffs and atheoretical groupings of individuals (e.g., stating that all people born between the early 1960s and early 1980s belong to Generation X). As noted by methodologists, this procedure leads to a loss of information about individuals and reduced statistical power (MacCallum, Zhang, Preacher, & Rucker, 2002). Due to these conceptual and methodological limitations, I regard it as very difficult if not impossible to develop a “comprehensive theory of generations” (Costanza & Finkelstein, p. 20) and to rigorously examine generational differences at work in empirical studies.

FactCheck: is our grocery market one of the most concentrated in the world?

With one of the most concentrated food retail sectors in the world dominated by the supermarket duopoly, the barriers to making it easy to buy local food in Australia are significant. It is time for Australia to learn from the example of other countries and provide assistance to rebuild local food systems.” – The Australian Greens. However, the percentage of market share controlled by the two major supermarkets, Coles and Woolworths, depends on which groceries you include.

The architecture of the psychiatric milieu

The last time a peer-reviewed volume on the future of mental health facilities was produced was in 1959, following a symposium organised by the American Psychological Association. The consensus was easy enough to follow and still resonates today: the best spaces to treat psychiatric illness will be in smaller, less restrictive units that offer more privacy and allow greater personalisation of space – possibly a converted hotel (Goshen, 1959). In some way, all those ideals have come to pass. An ideal typology was never established, but even so, units have shrunk from thousands of beds to units that typically house no more than 50 patients. Patients are generally more independent and are free to wander (within a unit) as they please. But the trend toward smaller and freer is reversing. This change is not driven by a desire to find the ideal building nor better models of care, but by growing concerns about budgets, self-harm and psychiatric violence. This issue of the Facilities comes at a time when the healthcare design is increasingly dominated by codes, statutes and guidelines. But the articles herein are a call to stop and think. We are not at the point where guidelines can be helpful, because they do not embody any depth of knowledge nor wisdom. These articles are intended to inject some new research on psychiatric/environmental interactions and also to remind planners and managers that guidelines might not tackle a core misunderstanding: fear-management about patient safety and the safety of society is not the purpose of the psychiatric facility. It is purpose is to create spaces that are suitable for improving the well-being of the mentally ill.

Inculcating character education through EFL teaching in Indonesian state schools

This paper describes how English as foreign language (EFL) teachers in Indonesia have implemented the recent character education policy within an era of school-based curriculum reform. The character education policy required all teachers, EFL teachers included, to instill certain values in every lesson whilst the school-based curriculum reform permitted teachers to develop locally responsive curriculum content. The design behind the reform seeks to sharpen education’s role as a site of moral inculcation in the face of growing social diversity that threatens social cohesion and the prolonged social problem of massive corruption. Drawing on Durkheim’s (1925) distinction between secular and religious morality, this paper considers how the Indonesian curriculum promoted rational or secular moral education and how the EFL teachers enacted religious moral education given religiosity is salient in both the community and schools of Indonesia. Bernstein’s concepts of pedagogic discourse, instructional and regulative discourses were adopted to analyse how EFL teachers have re-contextualized both curricular reforms in their micro pedagogic settings. The conclusion suggests that teachers’ implementation of moral education in their classes was dominated by their school communities’ and the teachers’ own preferred value of religiosity. Such values played out in their classes through both the regulative discourse and the instructional discourse.

Free energy calculations of glycosaminoglycan - Protein interactions

Glycosaminoglycans (GAGs) are complex highly charged linear polysaccharides that have a variety of roles in biological processes. We report the first use of molecular dynamics (MD) free energy calculations using the MM/PBSA method to investigate the binding of GAGs to protein molecules, namely the platelet endothelial cell adhesion molecule 1 (PECAM-1) and annexin A2. Calculations of the free energy of the binding of heparin fragments of different sizes reveal the existence of a region of low GAG-binding affinity in domains 5-6 of PECAM-1 and a region of high affinity in domains 2-3, consistent with experimental data and ligand-protein docking studies. A conformational hinge movement between domains 2 and 3 was observed, which allows the binding of heparin fragments of increasing size (pentasaccharides to octasaccharides) with an increasingly higher binding affinity. Similar simulations of the binding of a heparin fragment to annexin A2 reveal the optimization of electrostatic and hydrogen bonding interactions with the protein and protein-bound calcium ions. In general, these free energy calculations reveal that the binding of heparin to protein surfaces is dominated by strong electrostatic interactions for longer fragments, with equally important contributions from van der Waals interactions and vibrational entropy changes, against a large unfavorable desolvation penalty due to the high charge density of these molecules.

Social processes of health and physical education teachers’ identity formation: Reproducing and changing culture

This paper examines Initial Teacher Education students’ experiences of participation in health and physical education (HPE) subject department offices and the impact on their understandings and identity formation. Pierre Bourdieu’s concepts of habitus, field, and practice along with Wenger’s communities of practice form the theoretical frame used in the paper. Data were collected using surveys and interviews with student‐teachers following their teaching practicum and analysed using coding and constant comparison. Emergent themes revealed students’ participation in masculine‐dominated sports, gendered body constructions, and repertoires of masculine domination. Findings are discussed in relation to their impact on student‐teachers’ learning, identity formation, and marginalizing practices in the department offices. Implications for teacher education and HPE are explored.

Ion exchange of sodium chloride and sodium bicarbonate solutions using strong acid cation resins in relation to coal seam water treatment

Coal seam gas production has resulted in the production of large volumes of associated water which contains dissolved salts dominated by sodium chloride and sodium bicarbonate. Ion exchange using synthetic resins has been proposed as a method for desalination of coal seam water to make it suitable for various beneficial reuse options. This study investigated the behaviour of solutions of sodium chloride and sodium bicarbonate with respect to exchange with Lanxess S108H strong acid cation (SAC) resin. Equilibrium isotherms were created for solutions of NaCl and NaHCO3 and an actual sample of coal seam water from the Surat Basin in southern Queensland. The exchange of sodium ions arising from sodium bicarbonate was found to be considerably more favourable than exchange of sodium ions from sodium chloride solutions. This latter behaviour was attributed to the secondary decomposition of bicarbonate species under acidic conditions which resulted in the evolution of carbon dioxide and formation of water. The isotherm profiles could not be satisfactorily fitted by a single isotherm model such as the Langmuir expression. Instead, two Langmuir equations had to be simultaneously applied in order to fit the sections of the isotherm attributable to sodium ion exchange from sodium bicarbonate and sodium chloride. The shape of the isotherm profile was dependent upon the ratio of sodium chloride to sodium bicarbonate in solution and there was a high degree of correlation between simulated and actual coal seam water solutions.

Hydrolysis and dispersion properties of aqueous Y2Si 2O7 suspensions

The dispersion of aqueous γ-Y2Si2O7 suspensions, which contain only one component but have a complex ion environment, was studied by the introduction of two different polymer dispersants, polyethylenimine (PEI) and polyacrylic acid (PAA). The suspension without any dispersant remains stable in the pH range of 9-11.5 because of electrostatic repulsion, while it is flocculated upon stirring due to the readsorption of hydrolyzed ions on the colloid surface. However, suspensions with 1 dwb% PEI exhibit greater stability in the pH range of 4-11.5. The addition of PEI shifts the isoelectric point (IEP) of the suspensions from pH 5.8 to 10.8. Near the IEP (pHIEP=10.8), the stability of the suspensions with PEI is dominated by the steric effect. When the pH is decreased to acid direction, the stabilization mechanism is changed from steric hindrance to an electrosteric effect little by little. PAA also has the effect of reducing the hydrolysis speed via a "buffer effect" in the basic pH range, but the lack of adsorption between the highly ionized anionic polymer molecules and the negative colloid particle surfaces shows no positive effect on hydrolysis of colloids and on the stabilization of Y2Si 2O7 suspensions.