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Meningitis is commonly caused by infection with a variety of bacterial or viral pathogens. Acute bacterial meningitis (ABM) can cause severe disease, which can progress rapidly to a critical life-threatening condition. Rapid diagnosis of ABM is critical, as this is most commonly associated with severe sequelae with associated high mortality and morbidity rates compared to viral meningitis, which is less severe and self-limiting. We have designed a microarray for detection and diagnosis of ABM. This has been validated using randomly amplified DNA targets (RADT), comparing buffers with or without formamide, in glass slide format or on the Alere ArrayTubeTM (Alere Technologies GmbH) microarray platform. Pathogen-specific signals were observed using purified bacterial nucleic acids and to a lesser extent using patient cerebral spinal fluid (CSF) samples, with some technical issues observed using RADT and glass slides. Repurposing the array onto the Alere ArrayTubeTM platform and using a targeted amplification system increased specific and reduced nonspecific hybridization signals using both pathogen nucleic and patient CSF DNA targets, better revealing pathogen-specific signals although sensitivity was still reduced in the latter. This diagnostic microarray is useful as a laboratory diagnostic tool for species and strain designation for ABM, rather than for primary diagnosis.

In the lower Murray-Darling Basin, most groundwater discharges to the floodplain of the River Murray. Most of the groundwater is of high salinity and therefore can transfer significant salt loads into the river. To mitigate saline groundwater intrusion into the river, salt interception schemes (SIS) have been commissioned since the early 1990s. The SIS intercept highsalinity groundwater flow adjacent to the river floodplain and the intercepted water is pumped to distant evaporation basins. The in-river transient electromagnetic (RTEM) geophysics technique can be used to infer saline groundwater discharge areas and to inform SIS locations. RTEM results have also been used, albeit qualitatively, in the monitoring and evaluation of the performance of SIS. A methodology for evaluating SIS performance has been developed based on the area above the cumulative frequency distribution (ACFD) of RTEM riverbed-only resistivities. In addition to RTEM maps and cross-sections, the ACFD characterises a river reach with a single number. Increases in ACFD, from pre- to post-SIS RTEM surveys, indicate the changing groundwater flow regime and the building of freshwater lenses.

The salinisation of major river systems in Australia, and in other countries, is primarily determined by the upward movement of saline water from regional aquifers into the river. The migration has been accelerated due to irrigation schemes and farming practices that have changed regional hydraulic gradients driving saline-water in aquifers towards the major drainage points in the landscape. In this paper, we describe results from a transient electromagnetic (TEM) system that has been deployed to monitor the influx of saline water through sub-riverbed sediments. The deployment was a floating arrangement of a commercial fast sampling (high resolution) TEM system that is sensitive to shallow (b50 m depth) resistivity variations. The technique has been extensively trialed around the River Murray town of Waikerie in South Australia. An initial series of surveys along a 40 km section of river showed a range of sub-riverbed resistivities between 1 and 20 Vm, with a top layer of about 10–15 Vm closely following the water depth. Regions of high-resistivity in the riverbed sediments correlated well with saline-aquifer borehole pumping locations, indicating a localized drawdown of fresher river water. Low-resistivity anomalies have been interpreted as regions of saline water influx into the river. The technique is now used for routine mapping in Australia, with over 800 km of the Murray surveyed, and has potential application to other major world river systems.

Increasing salinity in the River Murray is well documented and is of concern environmentally, economically and socially. The Murray Darling Basin Commission and the Mallee Catchment Management Authority engaged the authors to collect base-line in-stream NanoTEM data within the River Murray from Lock 1 to Mallee Cliffs (675 km). This is a new application of a high resolution fast sampling Transient Electro-Magnetic (TEM) system, towed behind a boat, taking soundings every seven to ten metres along the river. The observed NanoTEM response was interpreted against the current understanding of the regional hydrogeology and groundwater processes in and around the river. This paper summarises some of the results from this investigation. The observed response correlates strongly with previously mapped major changes in underlying lithostratigraphy along the Murray River, and with gaining and losing reaches of the river. The extensive length of the survey provides an insight into potential interactions between the river, floodplain and groundwater, but does not replace the need for focussed ground-truthing programs to examine specific correlations. This rapid, portable technique should be applicable outside the Murray-Darling Basin as well as at additional locations within the Basin.

Successful implementation of a salt interception schemes (SIS) requires monitoring to determine locations where the scheme needs revision. Current monitoring methods involve near-surface water-salinity measurements, which are affected by water-flow displacement. A survey method that can determine the salinity of water contained in the top few metres of alluvial sediments immediately beneath the river would be a more accurate tool for SIS monitoring. A fast sampling Transient EM technique is investigated as a potential tool for imaging the conductivity of the top 5m of sediment, and thus monitoring the Waikerie SIS in South Australia?s Riverland. A towed TEM array was used to collect 9km of data that shows resistive anomalies correlating with SIS production bores. The system has the advantage of being a small, manageable array and the short inversion time allows same-day interpretation.

A fast and informative tool was required for the delineation of stratigraphy and hydrology and for monitoring salinisation effects around the Stockyard Plains Disposal Basin, which is used as a storage lake for salt water pumped from aquifers close to the Murray River near the town of Waikerie, South Australia. Such salinisation effects include the formation of a perched saline water-table close to the disposal basin and consequent threats to local fresh-water lenses. Ground penetrating radar, direct current (DC) resistivity, time-domain EM (TEM) and low induction number frequency-domain EM (FEM) were compared in terms of efficiency and effectiveness at two survey locations near the Stockyard Plains Disposal Basin. Low induction number FEM measurements were fast to implement but suffered from a non-linear response with ground conductivity in high conductivity areas. Radar methods were ineffective due to high signal attenuation in the highly saline environment. Fast time-sampling TEM successfully depicted a perched saline water table related to leakage from the disposal basin, and was found to be the most useful technique for delineation of hydrogeology due to its high vertical resolution. DC resistivity was the slowest technique, but was found useful in imaging a fresh-water lens. Results from this study suggest that TEM and DC resistivity methods are useful tools for both fresh-water detection and hydrogeology monitoring in saline groundwater environments.

New Miocene and Quaternary foraminiferid faunas have been recovered from previously unrecorded localities onshore near Penguin and Strahan, and at nine offshore localities off northwestern, northeastern and southeastern Tasmania. Most Miocene benthic forms found in these samples are well known from other Tasmanian Tertiary sections but a few previously unreported taxa are recorded in Tasmania for the first time. Two samples from off northeastern Tasmania are Miocene. The sample from southeastern Tasmania is Early Miocene with Quaternary overlying it. Pebbles from Ocean Beach, north of Strahan, contain earliest Middle Miocene faunas. Other samples from off northeastern and northwestern Tasmania contain Quaternary faunas which probably reflect both periods of lower sea level and cool water and also periods of higher sea level and warmer water. These samples extend the range of Miocene calcareous sediments much farther south on both west and east coasts of Tasmania. They also reinforce the pattern of Tasmanian Neogene sedimentation cycles (earliest Early Miocene, latest Early-earliest Middle Miocene, midLate Pliocene) identified previously.

This paper examines the potential of using the FDHEM RESOLVE system as basis for mapping reaches of the river that contribute to elevated salt loads in the Murray River to the south east of Mildura in Victoria. The advantages of the airborne systems become more apparent when data coverage and acquisition costs are considered, particularly in a situation where a parallel swath approached is employed. This entails the acquisition of adjacent lines of EM data along the centre and along the margins of the river. We suggest this approach provides for a better understanding of recharge and discharge processes and links between the floodplain and the main-river channel. Compared with data acquired along the river alone, this study demonstrated our ability to use Helicopter EM data to map losing and gaining (from a salt load perspective) stretches of the river and to provide insight into which parts of the groundwater-floodplain system were significant contributors to river salt loads. The rapid acquisition of airborne EM data makes these systems more suited to providing temporal snapshots of a river-floodplain environment during dramatic climatic events, such as flooding.

Accurate, high resolution images of the top 10 to 50 metres of the earth’s surface potentially provide insights into the underlying hydrogeology that help us to understand, for example, the distribution of saline groundwater in the subsurface, or subtle changes in the distribution of clays in the top ten metres. This paper reviews the use of a commercially available fast-sampling TEM system in use in the surrounds of the River Murray system in southeastern Australia. This system has been used to collect data in a fairly standard TEM mode, i.e. discrete stations at fixed intervals along a line. Additionally results are shown using the system in a modified configuration, with much smaller transmitting and receiving antennae towed behind a boat, for example, with data collected in conjunction with a GPS in a “continuous” mode. This type of data provides a continuous electrical cross section with data points as close together as five metres apart, to a depth of at least ten metres.

A patient who presented with a new apparent seizure was found to have abnormal electrocardiographic findings, with classic features of the Brugada syndrome. He had spontaneous episodes of nonsustained ventricular tachycardia, easily inducible ventricular fibrillation at electrophysiological study in the absence of structural heart disease, and a negative neurological evaluation. These findings suggested that sustained ventricular arrhythmias known to be associated with the Brugada syndrome and resultant cerebral hypoperfusion, rather than a primary seizure disorder, were responsible for the event. Patients with the Brugada syndrome often present with sudden death or with syncope resulting from ventricular arrhythmias. In consideration of its variability in presentation sometimes mimicking other disorders, primary care physicians and internists should be aware of its often transient electrocardiographic features.

We describe the case of a patient who has a right atrial tachycardia and atrial fibrillation who was found to have a single site responsible for both. We recorded a tachycardia from this site with exit block into the remainder of the atria.

Bibliography: leaves 113-134., A brief review of the literature on the effects of nitrate and ammonium nitrogen sources on plant growth, and the assimilation of those nitrogen sources, has been presented. A water culture technique for the growth of maize was developed. The use of a gravel rooting medium with nutrients recycling through the rooting medium, and an iron supplement in the form of ferric citrate, resulted in superior growth of nitrate-fed plants in comparison to that observed with a hydroponic growth technique and a standard Long Ashton nutrient solution. The effects of nitrogen source on plant growth, organic nitrogen and inorganic nitrogen contents, and the rates of incorporation into nitrogenous compounds were studied. The observed differences were explained with reference to the effects of the various nitrogen sources on the physiology of the plants. The experimental techniques included assays of the enzymes nitrate reductase and glutamine synthetase, whole plant growth studies, and the analysis of nitrogenous compounds of xylem exudate and those extracted from the leaf blade, leaf base, and root regions of maize plants after feeding with a nutrient solution containing nitrogen as 15N.