Interactions between pedestrians and cyclists in the city centre

The city centre represents a complex environment for cycling with large volumes of pedestrians and motorised vehicles and frequent signalised intersections. Much of the previous literature has focused on cyclist-motor vehicle interactions because of the safety implications for cyclists, but there is increasing concern from pedestrians about the threats they perceive from cyclists. In the absence of objective data, this has the potential to lead to restrictions on cyclist access and behaviour. This presentation reports the development of a method to study the extent of cycling in the city centre and the frequency and nature of interactions between cyclists and pedestrians. Queensland is one of the few Australian jurisdictions that permits adults to cycle on the footpath and this was also of interest. 1992 cyclists were observed at six locations in the Brisbane city centre, during 7-9am, 9-11am, 2-4pm and 4-6pm on four weekdays in October 2010. The majority (85.5%) of cyclists were male, and 21.8% rode on the footpath. Females were more likely to travel on the footpath than males. One or more pedestrians were within 1m for 18.1% of observed cyclists, and one or more pedestrians were within 5m for 39.1% of observed cyclists. There were few conflicts, defined as an occasion where if no one took evasive action a collision would occur, between cyclists and pedestrians or vehicles (1.1% and 0.6% respectively) but they were more common for adolescents and riders not wearing (or not fastening) helmets.

Human neural cell interactions with orientated electrospun nanofibers in vitro

Aim: Electrospun nanofibers represent potent guidance substrates for nervous tissue repair. Development of nanofiber-based scaffolds for CNS repair requires, as a first step, an understanding of appropriate neural cell type-substrate interactions. Materials & methods: Astrocyte–nanofiber interactions (e.g., adhesion, proliferation, process extension and migration) were studied by comparing human neural progenitor-derived astrocytes (hNP-ACs) and a human astrocytoma cell line (U373) with aligned polycaprolactone (PCL) nanofibers or blended (25% type I collagen/75% PCL) nanofibers. Neuron–nanofiber interactions were assessed using a differentiated human neuroblastoma cell line (SH-SY5Y). Results & discussion: U373 cells and hNP-AC showed similar process alignment and length when associated with PCL or Type I collagen/PCL nanofibers. Cell adhesion and migration by hNP-AC were clearly improved by functionalization of nanofiber surfaces with type I collagen. Functionalized nanofibers had no such effect on U373 cells. Another clear difference between the U373 cells and hNP-AC interactions with the nanofiber substrate was proliferation; the cell line demonstrating strong proliferation, whereas the hNP-AC line showed no proliferation on either type of nanofiber. Long axonal growth (up to 600 µm in length) of SH-SY5Y neurons followed the orientation of both types of nanofibers even though adhesion of the processes to the fibers was poor. Conclusion: The use of cell lines is of only limited predictive value when studying cell–substrate interactions but both morphology and alignment of human astrocytes were affected profoundly by nanofibers. Nanofiber surface functionalization with collagen significantly improved hNP-AC adhesion and migration. Alternative forms of functionalization may be required for optimal axon–nanofiber interactions.

Influencing the experience of people in urban public places through mobile mediated interactions

This paper introduces our research on influencing the experience of people in urban public places through mobile mediated interactions. Information and communication technology (ICT) devices are sometimes used to create personal space while in public. ICT devices could also be utilised to digitally augment the urban space with non-privacy sensitive data enabling mobile mediated interactions in an anonymous way between collocated strangers. We present what motivates the research on digital augmentations and mobile mediated interactions between unknown urban dwellers, define the research problem that drives this study and why it is significant research in the field of pervasive social networking. The paper illustrates three design interventions enabling social pervasive content sharing and employing pervasive presence, awareness and anonymous social user interaction in urban public places. The paper concludes with an outlook and summarises the research effort.

Expressive interactions : tablet usability for young mobile learners

In this paper we examine the usability of tablets for students in middle school in the context of mobile environmental education. Our study focuses on the expressive qualities of three input methods – text, audio and drawing – and the extent to which these methods support on-task behaviour. In our study 28 small groups of children were given iPads and asked to record ecological observations from around their schoolyard. The effectiveness of the devices and their core utility for expressive, on-task data capture is assessed.

Core-shell microspheres with surface grafted poly(vinyl alcohol) as drug carriers for the treatment of hepatocellular carcinoma

Core(polyvinyl neodecanoate-ethylene glycol dimethacrylate)-shell(polyvinyl alcohol) (core (P(VND-EGDMA))-shell(PVA)) microspheres were developed by seeded polymerization with the use of conventional free radical and RAFT/MADIX mediated polymerization. Poly(vinyl pivalate) PVPi was grafted onto microspheres prepared via suspension polymerization of vinylneodecanoate and ethylene glycol dimethacrylate. The amount of grafted polymer was found to be independent from the technique used with conventional free radical polymerization and MADIX polymerization resulting into similar shell thicknesses. Both systems—grafting via free radical polymerization or the MADIX process—were found to follow slightly different kinetics. While the free radical polymerization resulted in a weight gain linear with the monomer consumption in solution the growth in the MADIX controlled system experienced a delay. The core-shell microspheres were obtained by hydrolysis of the poly(vinyl pivalate) surface grafted brushes to form poly(vinyl alcohol). During hydrolysis the microspheres lost a significant amount of weight, consistent with the hydrolysis of 40–70% of all VPi units. Drug loading was found to be independent of the shell layer thickness, suggesting that the drug loading is governed by the amount of bulk material. The shell layer does not appear to represent an obstacle to the drug ingress. Cell testing using colorectal cancer cell lines HT 29 confirm the biocompatibility of the empty microspheres whereas the clofazimine loaded particles lead to 50% cell death, confirming the release of the drug.

Controlling cell-material interactions with polymer nanocomposites by use of surface modifying additives

Polymer nanocomposites (NC) are fabricated by incorporating well dispersed nanoscale particles within a polymer matrix. This study focuses on elastomeric polyurethane (PU) based nanocomposites, containing organically modified silicates (OMS), as bioactive materials. Nanocomposites incorporating chlorhexidine diacetate as an organic modifier (OM) were demonstrated to be antibacterial with a dose dependence related to both the silicate loading and the loading of OM. When the non-antibacterial OM dodecylamine was used, both cell and platelet adhesion were decreased on the nanocomposite surface. These results suggest that OM is released from the polymer and can impact on cell behaviour at the interface. Nanocomposites have potential use as bioactive materials in a range of biomedical applications.

Non-invasive, quantitative analysis of drug mixtures in containers using spatially offset Raman spectroscopy (SORS) and multivariate statistical analysis

In this paper, spatially offset Raman spectroscopy (SORS) is demonstrated for non-invasively investigating the composition of drug mixtures inside an opaque plastic container. The mixtures consisted of three components including a target drug (acetaminophen or phenylephrine hydrochloride) and two diluents (glucose and caffeine). The target drug concentrations ranged from 5% to 100%. After conducting SORS analysis to ascertain the Raman spectra of the concealed mixtures, principal component analysis (PCA) was performed on the SORS spectra to reveal trends within the data. Partial least squares (PLS) regression was used to construct models that predicted the concentration of each target drug, in the presence of the other two diluents. The PLS models were able to predict the concentration of acetaminophen in the validation samples with a root-mean-square error of prediction (RMSEP) of 3.8% and the concentration of phenylephrine hydrochloride with an RMSEP of 4.6%. This work demonstrates the potential of SORS, used in conjunction with multivariate statistical techniques, to perform non-invasive, quantitative analysis on mixtures inside opaque containers. This has applications for pharmaceutical analysis, such as monitoring the degradation of pharmaceutical products on the shelf, in forensic investigations of counterfeit drugs, and for the analysis of illicit drug mixtures which may contain multiple components.

4-(4-Aminophenylsulfonyl)aniline-1,3-5-trinitrobenzene (1/2)

The asymmetric unit of the title co-crystalline 1:2 adduct C12H12N2O2 . 2(C6H3N3O6) contains two independent molecules of bis(4-aminophenyl)sulfone (the drug Dapsone) and four molecules of 1,3,5-trinitrobenzene and is extended into a two-dimensional hydrogen-bonded network structure through amino N-H...O hydrogen-bonding associations with nitro O- atom acceptors. In the two independent Dapsone molecules the inter-ring dihedral angles are 69.0(2) and 63.59(11)deg. Aromatic pi-pi interactions are also found between one of the Dapsone aromatic rings and a trinitrobenzene ring [minimum ring centroid separation 3.576(5)Ang.]. A 4-aminophenyl ring moiety of one of the Dapsone molecules and two nitro groups of a trinitrobenzene are disordered in a 50:50 ratio.

4-(4-Aminophenylsulfonyl)aniline-3,5-dinitrobenzoic acid (1/1)

In the title co-crystalline adduct of the drug Dapsone with 3,5-dinitrobenzoic acid, C~12~H~12~N~2~O~2~S . C~7~H~4~N~4~O~6~, the dihedral angle between the two aromatic rings of the Dapsone molecule is 75.4(2)deg. and those between these rings and that of the 3,5-dinitrobenzoic acid are 64.5(2) and 68.4(2)deg. A strong inter-species carboxylic acid O-H---N(amine) hydrogen-bond is found, which together with intermolecular amine N-H...O hydrogen-bonding associations with carboxyl, nitro and sulfone O-atom acceptors as well as weak pi-pi interactions between one of the Dapsone phenyl rings and the 3,5-dinitrobenzoic acid ring [minimum ring centroid separation 3.774(2)Ang.], give a two-dimensional network structure.

Models of South-East Asian organised crime drug operations in Queensland

In 2002, the United Nations Office on Drugs and Crime (UNODC) issued a report entitled Results of a pilot survey of forty selected organized criminal groups in sixteen countries which established five models of organised crime. This paper reviews these and other common organised crime models and drug trafficking models, and applies them to cases of South East Asian drug trafficking in the Australian state of Queensland. The study tests the following hypotheses: (1) South-East Asian drug trafficking groups in Queensland will operate within a criminal network or core group; (2) Wholesale drug distributors in Queensland will not fit consistently under any particular UN organised crime model; and (3) Street dealers will have no organisational structure. The study concluded that drug trafficking or importation closely resembles a criminal network or core group structure. Wholesale dealers did not fit consistently into any UN organised crime model. Street dealers had no organisational structure as an organisational structure is typically found in mid- to high-level drug trafficking.

Assessment of function and clinical utility of alcohol and other drug web sites : an observational, qualitative study

Background The increasing popularity and use of the internet makes it an attractive option for providing health information and treatment, including alcohol/other drug use. There is limited research examining how people identify and access information about alcohol or other drug (AOD) use online, or how they assess the usefulness of the information presented. This study examined the strategies that individuals used to identify and navigate a range of AOD websites, along with the attitudes concerning presentation and content. Methods Members of the general community in Brisbane and Roma (Queensland, Australia) were invited to participate in a 30-minute search of the internet for sites related to AOD use, followed by a focus group discussion. Fifty one subjects participated in the study across nine focus groups. Results Participants spent a maximum of 6.5 minutes on any one website, and less if the user was under 25 years of age. Time spent was as little as 2 minutes if the website was not the first accessed. Participants recommended that AOD-related websites should have an engaging home or index page, which quickly and accurately portrayed the site’s objectives, and provided clear site navigation options. Website content should clearly match the title and description of the site that is used by internet search engines. Participants supported the development of a portal for AOD websites, suggesting that it would greatly facilitate access and navigation. Treatment programs delivered online were initially viewed with caution. This appeared to be due to limited understanding of what constituted online treatment, including its potential efficacy. Conclusions A range of recommendations arise from this study regarding the design and development of websites, particularly those related to AOD use. These include prudent use of text and information on any one webpage, the use of graphics and colours, and clear, uncluttered navigation options. Implications for future website development are discussed.

Screening for alcohol and drug use in pregnancy

Objective - this study examined the clinical utility and precision of routine screening for alcohol and other drug use among women attending a public antenatal service. Study design - a survey of clients and audit of clinical charts. Participants and setting - clients attending an antenatal clinic of a large tertiary hospital in Queensland, Australia, from October to December 2009. Measurements and findings - data were collected from two sources. First, 32 women who reported use of alcohol or other drugs during pregnancy at initial screening were then asked to complete a full substance use survey. Second, data were collected from charts of 349 new clients who attended the antenatal clinic during the study period. Both sensitivity (86%, 67%) and positive predictive value (100%, 92%) for alcohol and other drug use respectively, were high. Only 15% of surveyed women were uncomfortable about being screened for substance use in pregnancy, yet the chart audit revealed poor staff compliance. During the study period, 25% of clients were either not screened adequately or not at all. Key conclusions and implications for practise - despite recommended universal screening in pregnancy and the apparent acceptance by our participants, alcohol and other drug (A&OD) screening in the antenatal setting remains problematic. Investigation into the reasons behind, and ways to overcome, the low screening rate could improve health outcomes for mothers and children in this at-risk group. Targeted education and training for midwives may form part of the solution as these clinicians have a key role in implementing prevention and early intervention strategies.

Youth alcohol and drug good practice guide 1 : a framework for youth alcohol and other drug practice

This Guide outlines a framework for working with young people whose AOD use creates significant vulnerability to current or future harm. The target audience is practitioners who work with young people who have problematic AOD use and the managers of these practitioners. Areas of content include the elements of a framework for AOD practice, an appreciation of the developmental, social and institutional location of young people, key concepts and understandings regarding good youth centered context responsive practice, and key policy constructs and directions.