NSAM-derived total surface area vs. SMPS-derived "mobility equivalent" surface area for different environmentally relevant aerosols

The surface area of inhaled particles deposited in the alveolar region, as reported by the TSI nanoparticle surface area monitor (NSAM), was compared with the corresponding value estimated by a TSI scanning mobility particle sizer (SMPS) for a range of environmentally relevant aerosols, including petrol emissions, ETS, laser printer emissions, cooking emissions and ambient aerosols. The SMPS values were based on a mobility size distribution assuming spherical particles using the appropriate size-dependent alveolar-deposition factors provided by the ICRP. In most cases, the two instruments showed good linear agreement. With petrol emissions and ETS, the linearity extended to over 103 μm2 cm-3. With printer emissions, there was good linearity up to about 300 μm2 cm-3 while the NSAM increasingly overestimated the surface area at higher concentrations. The presence of a nucleation event in ambient air caused the NSAM to over-estimate the surface area by a factor of 2. We summarize these results and conclude that the maximum number concentration up to which the NSAM is accurate clearly depends on the type of aerosol being sampled and provide guidance for the use of the instrument.

Transcription and expression of Plasmodium falciparum histidine-rich proteins in different stages and strains : implications for rapid diagnostic tests

Background: Although rapid diagnostic tests (RDTs) for Plasmodium falciparum infection that target histidine rich protein 2 (PfHRP2) are generally sensitive, their performance has been reported to be variable. One possible explanation for variable test performance is differences in expression level of PfHRP in different parasite isolates. Methods: Total RNA and protein were extracted from synchronised cultures of 7 P. falciparum lines over 5 time points of the life cycle, and from synchronised ring stages of 10 falciparum lines. Using quantitative real-time polymerase chain reaction, Western blot analysis and ELISA we investigated variations in the transcription and protein levels of pfhrp2, pfhrp3 and PfHRP respectively in the different parasite lines, over the parasite intraerythrocytic life cycle. Results: Transcription of pfhrp2 and pfhrp3 in different parasite lines over the parasite life cycle was observed to vary relative to the control parasite K1. In some parasite lines very low transcription of these genes was observed. The peak transcription was observed in ring-stage parasites. Pfhrp2 transcription was observed to be consistently higher than pfhrp3 transcription within parasite lines. The intraerythrocytic lifecycle stage at which the peak level of protein was present varied across strains. Total protein levels were more constant relative to total mRNA transcription, however a maximum 24 fold difference in expression at ring-stage parasites relative to the K1 strain was observed. Conclusions: The levels of transcription of pfhrp2 and pfhrp3, and protein expression of PfHRP varied between different P. falciparum strains. This variation may impact on the detection sensitivity of PfHRP2-detecting RDTs.

Review : "English language education across Greater China" by A. Feng

I have formally learned English from Year Four till the completion of my undergraduate study in China. Because of this personal history, I was keen to review this book and revisit English education in China. The list of contributors to the book includes Anwei Feng (editor) and his colleagues, who play an insider role in English language practice, research, and policy-making in ‘Greater China’. ‘Greater China’ according to Feng, can be defined as geographically close, demographically Chinese-dominated, and culturally, economically, and socio-politically interrelated countries and territories where Chinese is either the mother tongue or used as an official language.

Learning English by walking down the street

With internationalisation and globalisation, English has proliferated in urban spaces around the world. This creates new opportunities for EFL learning and teaching. An English literacy walk is one activity that can be used productively to capitalise on this potential. The activity has roots in: (i) long-established approaches to emergent literacy education for young children; and (ii) pedagogic projects inspired by recent research on linguistic landscapes. Drawing on these traditions, teachers can target reading outcomes involving code, semantic, pragmatic and critical knowledge and skills. We use the four resources model of literate practices to systematically map some of the potential of literacy walks in multilingual, multimodal linguistic landscapes. We suggest tasks and teacher questions that might be used for purposes of explicit teaching of reading during and after literacy walks. Although grounded in Taipei, our ideas might be of interest to EFL teachers in other globalised cities around the world.

The Arab Spring and social media audiences : English and Arabic Twitter users and their networks

Although popular media narratives about the role of social media in driving the events of the 2011 “Arab Spring” are likely to overstate the impact of Facebook and Twitter on these uprisings, it is nonetheless true that protests and unrest in countries from Tunisia to Syria generated a substantial amount of social media activity. On Twitter alone, several millions of tweets containing the hashtags #libya or #egypt were generated during 2011, both by directly affected citizens of these countries and by onlookers from further afield. What remains unclear, though, is the extent to which there was any direct interaction between these two groups (especially considering potential language barriers between them). Building on hashtag data sets gathered between January and November 2011, this article compares patterns of Twitter usage during the popular revolution in Egypt and the civil war in Libya. Using custom-made tools for processing “big data,” we examine the volume of tweets sent by English-, Arabic-, and mixed-language Twitter users over time and examine the networks of interaction (variously through @replying, retweeting, or both) between these groups as they developed and shifted over the course of these uprisings. Examining @reply and retweet traffic, we identify general patterns of information flow between the English- and Arabic-speaking sides of the Twittersphere and highlight the roles played by users bridging both language spheres.

In vitro biocompatibility of different polyester membranes

Nowadays, synthetic biodegradable polymers, such as aliphatic polyesters, are largely used in tissue engineering. They provide several advantages compared to natural materials which use is limited by immunocompatibility, graft availability, etc. In this work, poly(L-lactic) acid (PLLA), poly(DL-lactic) acid (PDLA), poly-epsilon-caprolactone (PCL), poly(L-lactic)-co-caprolactone (molar ratio 70/30) (PLCL) were selected because of their common use in tissue engineering. The membranes were elaborated by solvent casting. Membrane morphology was investigated by atomic force microscopy. The membranes were seeded with human fibroblasts from cell line CRL 2703 in order to evaluate the biocompatibility by the Alamar blue test. The roughness of the membranes ranged from 4 nm for PDLA to 120 nm and they presented very smooth surface except for PCL which beside a macroscopic structure due to its hydrophobicity. Human fibroblasts proliferated over 28 days on the membranes proving the non-in vitro toxicity of the materials and of the processing method. A further step will be the fabrication of three-dimensional scaffold for tissue engineering and the treatment of the scaffolds to augment cell adhesion.

Conceptual and thematic analysis of policies and guidelines on engineering asset management of different states in Australia

The role of government in developing policies and guidelines for asset management is becoming increasingly important especially in view of ageing infrastructure and increasing financial risks for building infrastructure. This paper reviews policies and guidelines developed by Australian state authorities against industry developed principles. It utilizes the software program Leximancer to; a) produce conceptual visualisations of the key themes and concepts embedded within state-wide policies and guidelines, and b) systematically compare the differing asset management foci between states. The analyses reveal mixed results in terms of policy priorities and guidelines for managing assets at a strategic level across states. This paper outlines a rigorous analytical methodology to inform specific policy changes.

Why are pedestrian crashes so different in developing countries? A review of relevant factors in relation to their impact in Ethiopia

Much is known about pedestrian behaviour and crash risk in developed countries. In contrast, the literature on pedestrian crash risk in developing countries reveals wide gaps in knowledge and understanding, and a comprehensive assessment is lacking. In particular, pedestrian behaviour in developing countries is fundamentally different in comparison to developed countries, and is influenced by a variety of less well understood contributing factors, leading to difficulty in modelling and predicting pedestrian crash risk and in turn identifying effective safety countermeasures. This paper provides a comprehensive synthesis of the factors known to influence pedestrian crash risk in developing countries, then focuses on Ethiopia as a specific example. The paper identifies where critical gaps in knowledge exist regarding pedestrian crash risk and associated behaviour in developing countries--a set of knowledge gaps which collectively are significant. The paper concludes by articulating a critical research path moving forward, with the aim to achieve an improved understanding of developing country pedestrian crash risk, and an ultimate goal of identifying effective pedestrian safety countermeasures suited to the unique challenges faced by transport system managers in developing countries.

The role of motivation and motivational strategies in Saudi students' communicative competence in English

This study explored how motivation and motivational strategies influence the communicative competence of students from Saudi Arabia. Participants included Saudi students enrolled in English courses in Australian educational institutions, and Saudi students living in Saudi Arabia studying in English language institutes in Saudi Arabia. Phase One involved interviews with16 participants. In Phase Two, 279 participants completed a questionnaire. Findings included differences between participants’ measured and self-reported communicative competence, with the Australian group having higher levels of measured and self-reported communicative competence. In addition, motivation teaching strategies were found to affect students’ motivation, but not their communicative competence.

Studies of the phase evolution of YBCO materials with different additives

Y123 samples with varying amounts of added Y211, PtO 2 and CeO 2 have been melt processed and quenched from temperatures between 960°C and 1100°C. The microstructures of the quenched samples have been characterized using a combination of x-ray diffractometry, optical microscopy, scanning electron microscopy, microprobe analysis, energy-dispersive x-ray spectroscopy and wavelength-dispersive x-ray spectroscopy. The Ba-Cu-O-rich melt undergoes complex changes as a function of temperature and time. A region of stability of BaCuO 2 (BC1) and BaCu 2O 2 (BC2) exists below 1040°C in samples of Y123 + 20 mol% Y211. Ba 2Cu 3O 5 is stabilized by rapid quenching but appears to separate into BC1 and BC2 at lower quenching rates. PtO 2 and CeO 2 additions affect the distribution and volume fractions of the two Ba-Cu-oxide phases.

A new method for quantifying the contribution of different critical agents on railway bridge deterioration

Railway Bridges deteriorate over time due to different critical factors including, flood, wind, earthquake, collision, and environment factors, such as corrosion, wear, termite attack, etc. In current practice, the contributions of the critical factors, towards the deterioration of railway bridges, which show their criticalities, are not appropriately taken into account. In this paper, a new method for quantifying the criticality of these factors will be introduced. The available knowledge as well as risk analyses conducted in different Australian standards and developed for bridge-design will be adopted. The analytic hierarchy process (AHP) is utilized for prioritising the factors. The method is used for synthetic rating of railway bridges developed by the authors of this paper. Enhancing the reliability of predicting the vulnerability of railway bridges to the critical factors, will be the significant achievement of this research.

Characterisation of two distinctly different processes associated with the electrocrystallization of microcrystals of phase I CuTCNQ (TCNQ= 7, 7, 8, 8-tetracyanoquinodimethane)

Semi-conducting phase I CuTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane), which is of considerable interest as a switching device for memory storage materials, can be electrocrystallized from CH3CN via two distinctly different pathways when TCNQ is reduced to TCNQ˙− in the presence of [Cu(MeCN)4]+. The first pathway, identified in earlier studies, occurs at potentials where TCNQ is reduced to TCNQ˙− and involves a nucleation–growth mechanism at preferred sites on the electrode to produce arrays of well separated large branched needle-shaped phase I CuTCNQ crystals. The second pathway, now identified at more negative potentials, generates much smaller needle-shaped phase I CuTCNQ crystals. These electrocrystallize on parts of the surface not occupied in the initial process and give rise to film-like characteristics. This process is attributed to the reduction of Cu+[(TCNQ˙−)(TCNQ)] or a stabilised film of TCNQ via a solid–solid conversion process, which also involves ingress of Cu+via a nucleation–growth mechanism. The CuTCNQ surface area coverage is extensive since it occurs at all areas of the electrode and not just at defect sites that dominate the crystal formation sites for the first pathway. Infrared spectra, X-ray diffraction, surface plasmon resonance, quartz crystal microbalance, scanning electron microscopy and optical image data all confirm that two distinctly different pathways are available to produce the kinetically-favoured and more highly conducting phase I CuTCNQ solid, rather than the phase II material.

Examining gender differences in drivers' thoughts and feelings about different outcomes of speeding: Implications for future anti-speeding messages

Speeding remains a pervasive road safety problem, increasing both crash frequency and severity. Advertising countermeasures which aim to change individuals’ attitudes and behaviours are a key component in the array of countermeasures aimed at reducing this risky behaviour. Enhancing individuals’ perceptions of the personal relevance of such messages is important for increasing persuasiveness. This study examined what males and females reported as the most concerning aspects associated with (i) receiving a speeding fine, (ii) losing one’s license, and (iii) being involved in a crash. For each of these outcomes, a range of specific and appropriate aspects were assessed. For instance, in relation to receiving a fine, individuals reported the extent to which they would, for example, feel concerned about losing demerit points and paying more in insurance premiums. An online survey of 751 drivers (579 males; 16-79 years) was administered. When controlling for age, overall significant gender differences were found in relation to two of the three outcomes; receiving a fine and being in a crash. Follow-up tests of univariate effects revealed that females consistently reported being significantly more concerned than males on all aspects. Thus, for being fined, females were significantly more concerned with, for example, being caught and receiving a ticket in the mail; while, for being in a crash, specific aspects included, for example, injuring/killing oneself and seeing oneself as not a good/safe driver. The findings are discussed in terms of their implications for developing well-targeted messages aimed at discouraging drivers from speeding.

Perspectives on Reconceptualizing Early Mathematics Learning

This introductory section provides an overview of the different perspectives on reconceptualizing early mathematics learning. The chapters provide a broad scope in their topics and approaches to advancing young children’s mathematical learning. They incorporate studies that highlight the importance of pattern and structure across the curriculum, studies that target particular content such as statistics, early algebra, and beginning number, and studies that consider how technology and other tools can facilitate early mathematical development. Reconceptualizing the professional learning of teachers in promoting young children’s mathematics, including a consideration of the role of play, is also addressed. Although these themes are diffused throughout the chapters, we restrict our introduction to the core focus of each of the chapters.