The cultivation of human retinal pigment epithelial cells on Bombyx mori silk fibroin

We have presently evaluated membranes prepared from Bombyx mori silk fibroin (BMSF), for their potential use as a prosthetic Bruch’s membrane and carrier substrate for human retinal pigment epithelial (RPE) cell transplantation. Porous BMSF membranes measuring 3 μm in thickness were prepared from aqueous solutions (3% w/v) containing poly(ethylene oxide) (0.09%). The permeability coefficient for membranes was between 3 and 9 × 10-5 cm/s by using Allura red or 70 kDa FITC-dextran respectively. Average pore size (± sd) was 4.9 ± 2.3 µm and 2.9 ± 1.5 µm for upper and lower membrane surfaces respectively. Optimal attachment of ARPE-19 cells to BMSF membrane was achieved by pre-coating with vitronectin (1 µg/mL). ARPE-19 cultures maintained in low serum on BMSF membranes for approximately 8 weeks, developed a cobble-stoned morphology accompanied by a cortical distribution of F-actin and ZO-1. Similar results were obtained using primary cultures of human RPE cells, but cultures took noticeably longer to establish on BMSF compared with tissue culture plastic. These findings encourage further studies of BMSF as a substrate for RPE cell transplantation.

Utility of an alternative bicycle commute route of lower proximity to motorised traffic in decreasing exposure to ultra-fine particles, respiratory symptoms and airway inflammation - a structured exposure experiment

Background: Bicycle commuting in an urban environment of high air pollution is known as a potential health risk, especially for susceptible individuals. While risk management strategies aimed to reduce motorised traffic emissions exposure have been suggested, limited studies have assessed the utility of such strategies in real-world circumstances. Objectives: The potential of reducing exposure to ultrafine particles (UFP; < 0.1 µm) during bicycle commuting by lowering interaction with motorised traffic was investigated with real-time air pollution and acute inflammatory measurements in healthy individuals using their typical, and an alternative to their typical, bicycle commute route. Methods: Thirty-five healthy adults (mean ± SD: age = 39 ± 11 yr; 29% female) each completed two return trips of their typical route (HIGH) and a pre-determined altered route of lower interaction with motorised traffic (LOW; determined by the proportion of on-road cycle paths). Particle number concentration (PNC) and diameter (PD) were monitored in real-time in-commute. Acute inflammatory indices of respiratory symptom incidence, lung function and spontaneous sputum (for inflammatory cell analyses) were collected immediately pre-commute, and one and three hours post-commute. Results: LOW resulted in a significant reduction in mean PNC (1.91 x e4 ± 0.93 x e4 ppcc vs. 2.95 x e4 ± 1.50 x e4 ppcc; p ≤ 0.001). Besides incidence of in-commute offensive odour detection (42 vs. 56 %; p = 0.019), incidence of dust and soot observation (33 vs. 47 %; p = 0.038) and nasopharyngeal irritation (31 vs. 41 %; p = 0.007), acute inflammatory indices were not significantly associated to in-commute PNC, nor were these indices reduced with LOW compared to HIGH. Conclusions: Exposure to PNC, and the incidence of offensive odour and nasopharyngeal irritation, can be significantly reduced when utilising a strategy of lowering interaction with motorised traffic whilst bicycle commuting, which may bring important benefits for both healthy and susceptible individuals.

Developing intercultural competence in pre-service teachers from Australia and Malaysia : insights from the “Patches” programme

Developing intercultural competence in pre-service teachers from Australia and Malaysia: Insights from a Patches program. Innovative pedagogies can offer pre-service teachers the opportunity to develop their intercultural competence and take up more globalised viewpoints. One such innovation is the Patches program which brought together Malaysian and Australian pre-service teachers who were studying at the same university in Brisbane, Australia, to actively explore issues of cultural and linguistic difference. The participants were 14 Australian fourth-year pre-service teachers who were enrolled in a program on inclusive education, and 58 Malaysian pre-service teachers who had recently arrived at the university in Brisbane to commence their second year of an international education program. In peer groupings, these domestic and international pre-service teachers engaged in a series of interactive tasks and reflective writing workshops exploring intercultural experiences, over a period of ten weeks. Each element or ‘patch’ in the program was designed to build up into a mosaic of intercultural learning. The flexible structuring of the Patches Program provided a supportive framework for participant interaction whilst allowing the groups to decide for themselves the nature and extent of their involvement in a series of community-related tasks. The process of negotiating and implementing these activities formed the basis for establishing meaningful relationships between the participants. The development of the participants’ intercultural competence is traced through their reflective narratives and focus group discussions, drawing on Byram’s concept of the five savoirs. Explaining aspects of Australian culture to their newly arrived Malaysian peers, allowed the Australian pre-service teachers to take a perspective of outsideness towards their own familiar social practices. In addition, being unusually positioned as the linguistic other amongst a group of Bahasa Melayu speakers, highlighted for the Australian pre-service teachers the importance of being inclusive. For the Malaysian pre-service teachers, participation in the Patches program helped to extend intercultural understandings, establish social networks with local students, and build a sense of community in their new learning environment. Both groups of pre-service teachers noted the power of “learning directly by interacting rather than through books”. In addition to interacting interculturally, the process of reflecting on these intercultural experiences is seen as integral to the development of intercultural competence.

The interface of the national Australian curriculum and the pre-Year 1 class in school : exploring tensions

The Australian state -based educational system of a national school curriculum that includes a pre-Year 1 Foundation Year has raised questions about the purpose of this year of early education. A document analysis was undertaken across three Australian states, examining three constructions of the pre-Year 1 class and tensions arising from varied perspectives. Tensions have emerged over state-based adaptations of the national curriculum, scripted pedagogies for change management, differing ideological perspectives and positioning of stakeholders. The results indicate that since 2012 there has been a shift in constructions of the pre-Year 1 class towards school-based ideologies, especially in Queensland. Accordingly, positioning of children, parents and teachers has also changed. These results resonate with previous international indications of ‘schooling’ early education. The experiences of Australian early adopters of the curriculum offer insights for other jurisdictions in Australia and internationally, and raise questions about future development in early years education.

Infrared and Raman spectroscopic characterization of the silicate-carbonate mineral carletonite – KNa4Ca4Si8O18(CO3)4(OH,F) H2O

Abstract An assessment of the molecular structure of carletonite a rare phyllosilicate mineral with general chemical formula given as KNa4Ca4Si8O18(CO3)4(OH,F)·H2O has been undertaken using vibrational spectroscopy. Carletonite has a complex layered structure. Within one period of c, it contains a silicate layer of composition NaKSi8O18·H2O, a carbonate layer of composition NaCO3·0.5H2O and two carbonate layers of composition NaCa2CO3(F,OH)0.5. Raman bands are observed at 1066, 1075 and 1086 cm−1. Whether these bands are due to the CO32- ν1 symmetric stretching mode or to an SiO stretching vibration is open to question. Multiple bands are observed in the 300–800 cm−1 spectral region, making the attribution of these bands difficult. Multiple water stretching and bending modes are observed showing that there is much variation in hydrogen bonding between water and the silicate and carbonate surfaces.

Communicating in the pre-hospital emergency environment

Aim. To develop and evaluate the implementation of a communication board for paramedics to use with patients as an augmentative or alternative communication tool to address communication needs of patients in the pre-hospital setting. Method. A double-sided A4-size communication board was designed specifically for use in the pre-hospital setting by the Queensland Ambulance Service and Disability and Community Care Services. One side of the board contains expressive messages that could be used by both the patient and paramedic. The other side contains messages to support patients’ understanding and interaction tips for the paramedic. The communication board was made available in every ambulance and patient transport vehicle in the Brisbane Region. Results. A total of 878 paramedics completed a survey that gauged which patient groups they might use the communication board with. The two most common groups were patients from culturally and linguistically diverse backgrounds and children. Staff reported feeling confident in using the board, and 72% of interviewed paramedics agreed that the communication board was useful for aiding communication with patients. Feedback from paramedics suggests that the board is simple to use, reduces patient frustration and improves communication. Conclusion. These results suggest that a communication board can be applied in the pre-hospital setting to support communication success with patients. What is known about the topic? It is imperative that communication between patient and paramedic is clear and effective. Research has shown that communication boards have been effective with people with temporary or permanent communication difficulties. What does this paper add? This is the first paper outlining the development and use of a communication board by paramedics in the pre-hospital setting in Australia. The paper details the design of the communication board for the unique pre-hospital environment. The paper provides some preliminary data on the use of the communication board with certain patient groups and its effectiveness as an alternative communication tool. What are the implications for practitioners? The findings support the use of the tool as a viable option in supporting the communication between paramedics and a range of patients. It is not suggested that this communication board will meet the complete communication needs of any individual in this environment, but it is hoped that the board’s presence within the Queensland Ambulance Service may result in paramedics introducing the board on occasions where communication with a patient is challenging.

Explaining Pathe's global dominance in the pre-Hollywood film industry

For almost a decade before Hollywood existed, French firm Pathe towered over the early film industry with estimates of its share of all films sold around the world varying between 50-70%. This paper analyses Pathe’s rise to market leadership by applying a theoretical framework drawn from the business literature on causes of industry dominance, that provides insights into how firms acquire and maintain market dominance. This paper uses evidence presented by film historians to argue that Pathe “fits” the expected theoretical model of the dominant firm because it had a marketing orientation, used an effective quality- based competitive strategy and possessed the six critical strategic marketing capabilities that business research shows enable the best performing firms to consistently outperform rivals.

Numerical analysis of shape transition in graphene nanoribbons

Graphene nanoribbon (GNR) with free edges can exhibit non-flat morphologies due to pre-existing edge stress. Using molecular dynamics (MD) simulations, we investigate the free-edge effect on the shape transition in GNRs with different edge types, including regular (armchair and zigzag), armchair terminated with hydrogen and reconstructed armchair. The results show that initial edge stress and energy are dependent on the edge configurations. It is confirmed that pre-strain on the free edges is a possible way to limit the random shape transition of GNRs. In addition, the influence of surface attachment on the shape transition is also investigated in this work. It is found that surface attachment can lead to periodic ripples in GNRs, dependent on the initial edge configurations.

Molecular dynamics simulation of fracture strength and morphology of defective graphene

Different types of defects can be introduced into graphene during material synthesis, and significantly influence the properties of graphene. In this work, we investigated the effects of structural defects, edge functionalisation and reconstruction on the fracture strength and morphology of graphene by molecular dynamics simulations. The minimum energy path analysis was conducted to investigate the formation of Stone-Wales defects. We also employed out-of-plane perturbation and energy minimization principle to study the possi-ble morphology of graphene nanoribbons with edge-termination. Our numerical results show that the fracture strength of graphene is dependent on defects and environmental temperature. However, pre-existing defects may be healed, resulting in strength recovery. Edge functionalization can induce compressive stress and ripples in the edge areas of gra-phene nanoribbons. On the other hand, edge reconstruction contributed to the tensile stress and curved shape in the graphene nanoribbons.

World's pre-eminent powers recent treatment to international law : a paradigm of interest served or harmed

The US's recent rejection of some international laws may have been done to ensure American interests but it may have the opposite effects. While its recent rejection of some international legal arrangements has meant an unpopular opinion of America, its interest has been served.

A new model to study healing of a complex femur fracture with concurrent soft tissue injury in sheep

High energy bone fractures resulting from impact trauma are often accompanied by subcutaneous soft tissue injuries, even if the skin remains intact. There is evidence that such closed soft tissue injuries affect the healing of bone fractures, and vice versa. Despite this knowledge, most impact trauma studies in animals have focussed on bone fractures or soft tissue trauma in isolation. However, given the simultaneous impact on both tissues a better understanding of the interaction between these two injuries is necessary to optimise clinical treatment. The aim of this study was therefore to develop a new experimental model and characterise, for the first time, the healing of a complex fracture with concurrent closed soft tissue trauma in sheep. A pendulum impact device was designed to deliver a defined and standardised impact to the distal thigh of sheep, causing a reproducible contusion injury to the subcutaneous soft tissues. In a subsequent procedure, a reproducible femoral butterfly fracture (AO C3-type) was created at the sheep’s femur, which was initially stabilised for 5 days by an external fixator construct to allow for soft tissue swelling to recede, and ultimately in a bridging construct using locking plates. The combined injuries were applied to twelve sheep and the healing observed for four or eight weeks (six animals per group) until sacrifice. The pendulum impact led to a moderate to severe circumferential soft tissue injury with significant bruising, haematomas and partial muscle disruptions. Posttraumatic measurements showed elevated intra-compartmental pressure and circulatory tissue breakdown markers, with recovery to normal, pre-injury values within four days. Clinically, no neurovascular deficiencies were observed. Bi-weekly radiological analysis of the healing fractures showed progressive callus healing over time, with the average number of callus bridges increasing from 0.4 at two weeks to 4.2 at eight weeks. Biomechanical testing after sacrifice showed increasing torsional stiffness between four and eight weeks healing time from 10% to 100%, and increasing ultimate torsional strength from 10% to 64% (relative to the contralateral control limb). Our results demonstrate the robust healing of a complex femur fracture in the presence of a severe soft tissue contusion injury in sheep and demonstrate the establishment of a clinically relevant experimental model, for research aimed at improving the treatment of bone fractures accompanied by closed soft tissue injuries.

Oropharyngeal dysphagia in an elderly post-operative hip fracture population : a prospective cohort study

Background: normal ageing processes impact on oropharyngeal swallowing function placing older adults at risk of developing oropharyngeal dysphagia (OD). Anecdotal clinical experience has observed that older patients recovering from hip fracture surgery commonly develop OD post-operatively. Objective: to document the presence of OD following hip fracture surgery, and the factors associated with OD. Methods: one hundred and eighty-one patients with a mean age of 83 years (range: 65–103) admitted to a specialised orthogeriatric unit were assessed for OD post-surgery for hip fracture. Pre-admission, intra-operative and post-operative factors were examined to determine their relationship with the presence of OD. Results: OD was found to be present post-operatively in 34% (n = 61) of the current population. Multivariate logistic regression analyses revealed the presence of pre-existing neurological and respiratory medical co-morbidities, presence of post-operative delirium, age and living in a residential aged care facility prior to hospital admission to be associated with the post-operative OD. Conclusion: these results highlight that OD is present in a large number of the older hip fracture population. Early identification of OD has important implications for the provision of timely dysphagia management that may prevent secondary complications and potentially reduce the hospital length of stay.

Education for sustainability : a case study of pre-service primary teachers' knowledge and efficacy

This study investigated the relationships between knowledge and efficacy for teaching sustainability in a sample of 266 pre-service primary teachers at a large, metropolitan university in Australia. A survey gathered information about the participant’s attitudes and self-efficacy for education for sustainability, along with their perceived and actual knowledge of environmental sustainability issues. The participants typically believed they were confident in their abilities to engage with education for sustainability with self-efficacy increasing with increased levels of perceived knowledge. However no relationship was found between perceived knowledge and actual knowledge which suggests that the participants either do not feel constrained by their lack of knowledge, or are perhaps unaware of their actual knowledge of sustainability issues. This lack of relationship may have implications for the development of pedagogical content knowledge with pre-service teachers potentially developing shallow, tokenistic approaches to Education for Sustainability.

An FE investigation simulating intra-operative corrective forces applied to correct scoliosis deformity

Background: Adolescent idiopathic scoliosis (AIS) is a deformity of the spine, which may 34 require surgical correction by attaching a rod to the patient’s spine using screws 35 implanted in the vertebral bodies. Surgeons achieve an intra-operative reduction in the 36 deformity by applying compressive forces across the intervertebral disc spaces while 37 they secure the rod to the vertebra. We were interested to understand how the 38 deformity correction is influenced by increasing magnitudes of surgical corrective forces 39 and what tissue level stresses are predicted at the vertebral endplates due to the 40 surgical correction. 41 Methods: Patient-specific finite element models of the osseoligamentous spine and 42 ribcage of eight AIS patients who underwent single rod anterior scoliosis surgery were 43 created using pre-operative computed tomography (CT) scans. The surgically altered 44 spine, including titanium rod and vertebral screws, was simulated. The models were 45 analysed using data for intra-operatively measured compressive forces – three load 46 profiles representing the mean and upper and lower standard deviation of this data 47 were analysed. Data for the clinically observed deformity correction (Cobb angle) were 48 compared with the model-predicted correction and the model results investigated to 49 better understand the influence of increased compressive forces on the biomechanics of 50 the instrumented joints. 51 Results: The predicted corrected Cobb angle for seven of the eight FE models were 52 within the 5° clinical Cobb measurement variability for at least one of the force profiles. 53 The largest portion of overall correction was predicted at or near the apical 54 intervertebral disc for all load profiles. Model predictions for four of the eight patients 55 showed endplate-to-endplate contact was occurring on adjacent endplates of one or 56 more intervertebral disc spaces in the instrumented curve following the surgical loading 57 steps. 58 Conclusion: This study demonstrated there is a direct relationship between intra-59 operative joint compressive forces and the degree of deformity correction achieved. The 60 majority of the deformity correction will occur at or in adjacent spinal levels to the apex 61 of the deformity. This study highlighted the importance of the intervertebral disc space 62 anatomy in governing the coronal plane deformity correction and the limit of this 63 correction will be when bone-to-bone contact of the opposing vertebral endplates 64 occurs.

Numerical Characterization of Nanowires

In this chapter, we will present a contemporary review of the hitherto numerical characterization of nanowires (NWs). The bulk of the research reported in the literatures concern metallic NWs including Al, Cu, Au, Ag, Ni, and their alloys NWs. Research has also been reported for the investigation of some nonmetallic NWs, such as ZnO, GaN, SiC, SiO2. A plenty of researches have been conducted regarding the numerical investigation of NWs. Issues analyzed include structural changes under different loading situations, the formation and propagation of dislocations, and the effect of the magnitude of applied loading on deformation mechanics. Efforts have also been made to correlate simulation results with experimental measurements. However, direct comparisons are difficult since most simulations are carried out under conditions of extremely high strain/loading rates and small simulation samples due to computational limitations. Despite of the immense numerical studies of NWs, a significant work still lies ahead in terms of problem formulation, interpretation of results, identification and delineation of deformation mechanisms, and constitutive characterization of behavior. In this chapter, we present an introduction of the commonly adopted experimental and numerical approaches in studies of the deformation of NWs in Section 1. An overview of findings concerning perfect NWs under different loading situations, such as tension, compression, torsion, and bending are presented in Section 2. In Section 3, we will detail some recent results from the authors’ own work with an emphasis on the study of influences from different pre-existing defect on NWs. Some thoughts on future directions of the computational mechanics of NWs together with Conclusions will be given in the last section.