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Inspections of engineered structures below water level are essential to ensure the long-term serviceability of bridge infrastructure and to avoid major damage or failure. This research aimed to investigate integrated geophysical technologies for the underwater inspection of bridge foundation-related scour and erodible scour-based infill. Survey methods focused on Water-Penetrating Radar (WPR), supplemented by sonar. Whilst the survey benefits of the sonar imaging water–sediment interface and structures are well known, those of WPR are not. However, it is ideally suited to the survey of the water base and sub-sediment in shallow (>10 m) freshwater, especially where suspended sediment, weed infestation or methane impede sonar results. Our work produced good WPR imagery acquired from small, manoeuvrable boats that allowed bathymetric profiles to be plotted, as well as the likely locations of soft-sediment scour in future high-water flow events. This study provides clear benefits for integrated sonar and WPR surveys in the quantitative assessment of engineered structures within freshwater.

An 81-year-old man was referred to the cardiology clinic with breathlessness and angina. His history included triple-vessel coronary artery bypass graft (CABG) plus St Jude Epic 21 mm bioprosthetic aortic valve replacement (AVR) surgery 7 years prior. Transthoracic echocardiography (TTE) demonstrated severely elevated Doppler AVR velocities (VMax 4.7 m/s) and severe AVR stenosis (valve area 0.7cm2). This was the suspected cause of symptoms, and transfemoral valve-in-valve AVR valve-in-valve transcatheter aortic valve implantation (VIV-TAVI) was being considered. However, TTE image quality was suboptimal due to echocardiographic windows and valve echogenicity, precluding accurate leaflet assessment (figure 1A–D). Transoesophageal echocardiography corroborated TTE findings (VMax 5.5 m/s) but failed to delineate the mechanism of AVR restriction (figure 1E–H). Degenerative leaflet calcification was evident on echocardiography, however echogenicity around the sewing ring prevented distinction between calcification and pannus, and ultrasound dropout precluded thrombus exclusion. Figure 1 Top row (transthoracic echocardiography): (A) Parasternal long-axis view with limited AVR visualisation (open-headed arrow) with increased echogenicity which can be due to pannus, calcification or metallic valve components; (B) turbulent antegrade colour-Doppler flow; (C) apical five-chamber view with limited AVR visualisation (open-headed arrow); (D) severely elevated antegrade AVR velocities on continuous-wave Doppler (VMax 4.6 m/s) suggestive of severe valve stenosis/obstruction. Bottom row (transoesophageal echocardiography): (E-G) …

This article analyses the status and future of bilingual education programs using Indigenous languages and English in remote Northern Territory schools. It explains why this educational approach is so contested at present, resulting in an unresolved situation which can best be regarded as an uneasy compromise on the ground and a stalemate at higher levels of political decision making. If the bilingual education approach was better understood by the current NT Government, there would a strong impetus now to refine and effectively implement a model of schooling that is appropriate for students in remote areas. Instead, current politicians debunk the bilingual approach, thereby robbing schools and literacy plans of any momentum and distracting attention away from the work that needs to be done. Meanwhile, student attendance rates have fallen away to worryingly low levels (Dickson, 2010). The current regime may well resolve the impasse, but in the absence of any meaningful, open negotiation the future looks uncertain. It is too soon to judge the cost of this uncertainty, but it may well result in further alienation and the emergence of non-government alternatives.

A crucial question in cross-cultural education is how to bridge the cultural and linguis- tic differences between home and school so that a child’s identity can be supported without limiting his or her chances of academic success (Eades, 1991). Various models of bilingual education have been implemented in Aboriginal communities in the Northern Territory of Australia but the implementation of such programmes is often far from ideal. In the school where this ethnographic study was conducted, miscom- munication between Aboriginal students and their non-Aboriginal teachers was found to be commonplace. Even by late primary school, children often did not comprehend classroom instructions in English. In addition, many students attended school irregu- larly, and many had a history of mild hearing loss due to otitis media (middle ear infection) which is highly prevalent in Australian Aboriginal communities. Cultural differences in communication were not easily differentiated from hearing-related communication problems by non-Aboriginal educators. These difficulties were exac- erbated by the lack of specialist support and appropriate training for teachers in cross-cultural communication and ESL teaching. Although the Aboriginal teaching assistants were often effective in minimising communication breakdown, the extent of miscommunication severely inhibited the children’s education when English was the language of instruction and interaction. The problem identified is one that should be of major concern to all concerned with Aboriginal education.