The effectiveness of post-fire weed management and the germination ecology of selected invasive weed species of Bold Park

Bold Park is a 437 hectare A class reserve with high conservation value. Bold park is located on the Swan Coastal Plain, approximately 11 km west of the Perth CBD. Bold park is one of the few remaining coastal bushland reserves on the Swan Coastal Plain. High levels of floristic and faunal diversity contribute to Bold Park\u27s conservation value. Weed invasion in Bold Park is reducing floristic diversity and is modifying ecosystem processes. Principle in the modified ecosystem processes is fire. While fire is a natural disturbance event in the bushland of the south-west of Western Australia, altered fire regimes can lead to weed invasion. Fire events are important for the maintenance of the floristic diversity of bushland areas. Fire events also provide an opportunity for weed management activities to be implemented. A fire in December 2000 burnt over one third of the bushland area in Bold Park. This provided managers from the Botanic Gardens and Parks Authority with the opportunity to implement weed control activities. Three approaches to weed management were undertaken within the 2000 burn site. They are: 1. No management; 2. Control of the invasive weed Pelargonium capitatum with the broadleaf herbicides Aimtm and Rounduptm; and 3. Control of the invasive grass Ehrharta calycina with the grass-specific herbicide Fusiladetm, along with the two broadleaf herbicides. To determine whether the weed spraying was successful, vegetation surveys were undertaken in the treatment areas of the 2000 burn site to investigate floristic differences. Significant reductions in weed species cover were detected in sites receiving both types of herbicides. Native species richness was highest in sites in receiving some form of weed control. However, this was accompanied by an increase in the richness of weed species. There was a significant difference in the cover of P. capitatum and E. calycina in relation to weed control measures. Where Fusilade was used; the cover of E. calycina was significantly lower than areas not sprayed with the herbicide. Where Aim and Roundup were used; there was a significant reduction in the cover of P. capitatum. Weed control measures were also linked to increases in the diversity, abundance and survival of native species recruits. A second study provided supplementary information on weed management by investigating the germination ecology of three weed species, E. calycina, P. capitatum and Euphorbia terracina. The seeds of these species all fit broad generalisations about weed seeds. They all have high levels of viability, easily overcome dormancy mechanisms and high levels of germination. The results obtained in this research indicate that post-fire weed control had immediate and significant effects in the Bold Park bushland. The long-term benefits of effective weed control would be a continued reduction in weed cover in the 2000 burn site. This reduction would enhance native species recruitment, leading to improvements in the floristic and vegetative community structure. The potential for future fire events would be reduced due to the lower E. calycina cover, a sound reason for expanding management of this species. Finally, the germination ecology of the weeds studied enhances the understanding of the invasive capacity of these species

PADAL-Passive Acoustic Detection and Localisation: Low energy underwater wireless vessel tracking network

This paper presents the development of a low energy wireless Passive Acoustic Detection And Localisation (PADAL) vessel tracking system. The purpose of this technology is to exploit propeller cavitation noise to detect and track vessel activity using a small acoustic receiver array. The PADAL system uses two main techniques in an energy conservation hierarchical approach to perform very low energy detection followed by higher energy bearing estimation which can enable localisation given multiple PADAL nodes. A low energy implementation of Detection of Envelope Modulation On Noise (DEMON) algorithm is used to identify a vessel in the area. This is followed by a generalised cross-correlation phase transform (GCC-PHAT) method of estimating the bearing the vessel using the receiver array. Experiments have been conducted under very controlled conditions using recordings of a known vessel processed offline. These experiments have aided the development of both detection and bearing estimate algorithms and results have shown the ability to detect and estimate the bearing of vessels using a small three element array with minimal signal processing to conserve energy. Using these positive results a PADAL prototype unit has been developed which is based on a custom analogue front end amplifier and Arm Cortex M4 processor. This system has been successfully tested at sea utilising a custom LoRaWAN two-way transparent serial link gateway buoy to receive data and modify tuning parameter in real time. The initial field trial results have shown the PADAL unit can autonomously detect and then estimate the bearing of a vessel with data relayed back to shore in real time. Future work will include a redevelopment of the PADAL hardware to move away from a prototype stage in an effort to minimise power consumption. The ultimate long term goal of the project is to deploy multiple PADAL nodes to establish a underwater sensor network to detect and track vessel activity in and out of a local port with data validation provided by the local port authority

A thematic analysis assessing clinical decision-making in antipsychotic prescribing for schizophrenia

Abstract Background In recent decades atypical antipsychotics have increased treatment options available for schizophrenia, however there is conflicting evidence concerning the trade-off between clinical efficacy and side effects for the different classes of antipsychotics. There has been a consistent increase in atypical antipsychotic prescribing compared to typical, despite evidence showing that neither class is superior. This leads to the question of whether prescribers are selective in their uptake of research evidence and clinical guidelines and if so, what influences their choice.. This study aims to identify the factors that contribute to the prescribing choice and how these can be used to aid knowledge translation and guideline implementation. Methods A thematic analysis study was conducted using data from 11 semi-structured interviews with clinicians with experience in prescribing for schizophrenia. Results The analysis identified five themes underpinning prescribing behaviour: (1) ownership and collaboration; (2) compromise; (3) patient involvement; (4) integrating research evidence; and (5) experience. Conclusion The themes mapped to various degrees onto current models of evidence-based decision making and suggest that there is scope to re-think the guideline implementation frameworks to incorporate recurring themes salient to clinicians who ultimately use the guidelines. This will further translation of future evidence into clinical practice, accelerating clinical progress

A quantitative analysis of antipsychotic prescribing trends for the treatment of schizophrenia in England and Wales

Objective This study aims to assess the current antipsychotic prescribing trends for the treatment of schizophrenia and to compare them with available guidelines and research evidence. Design An observational retrospective quantitative analysis. Setting Data were collected from the prescribing cost analysis for the period between 2007 and 2014, including all drugs from the British National Formulary 4.2.1 and 4.2.2. Prescriptions were included from primary and secondary healthcare settings in England and Wales. Participants None. Main outcome measures Defined daily doses of antipsychotics were used to compare popularity of individual drugs and classes of antipsychotics. Results There is a consistent increase in the proportion of atypical antipsychotics prescribed, compared to typical antipsychotics, between 2007 and 2014, with atypicals accounting for 79.9% of total antipsychotics prescribed in 2014. Conclusion The consistent popularity of atypical antipsychotics is not concordant with the current National Institute for Health and Care Excellence guidelines for the treatment of schizophrenia or the most recent research evidence. </jats:sec

Pervasive wireless sensors: A new monitoring tool for road traffic noise evaluation

Noise pollution is estimated to affect 170 million citizens in Europe, causing serious public health problems [1]. The World Health Organisation claims that at least one million healthy life years are lost per year in Europe due to road traffic noise [2]. Effective management of noise requires an understanding of its causes. This understanding is limited by traditional monitoring methods, which employ expensive equipment and are labour intensive. This paper presents the results of a comprehensive programme of correction and validation of a low-cost device referred to as an eMote for pervasive monitoring and is the first to quantify the accuracy of inexpensive noise systems that use microphones typically costing about one Euro. Pervasive wireless noise sensors (eMotes) were validated by co-location with precision sound level meters in controlled indoor, and at roadside outdoor environments. Strong linear relationships between the eMotes and the precision systems, across a noise range between 55 dBA and 94 dBA were observed and exhibited consistent bias compared to the precision measurement. Therefore, a generic, corrective relationship was derived and validated in three contrasting outdoor traffic noise environments, employing both short-term attended, and long-term unattended measurements, which were carried out during day and/or evening and/or night periods. The eMotes were shown to respond consistently to white and pink generated noise during the evaluation of the accuracy process, and the generic correction algorithm for white noise delivered better than 3 dBA accuracy in comparison to precision data at a one-minute averaging resolution. The correction algorithm improved the concordance correlation coefficient (ccc) and coefficient of determination (R2) of the eMote measurements against those of the precision instrument. Removal of short-duration, excessively loud events (e.g. sirens), which represented 2% of the total data, improved the ccc and R2 values further typically to 0.74 and 0.60 respectively, which is considered good, given the limitations of the experimental procedure. The research provides scientific evidence that whilst not acceptable for compliance monitoring to standards for noise exposure, the eMote is a valuable system to screen for excessive exposure; to understand the causes of traffic related noise in urban areas; to provide an indication of the spatial and temporal variation in noise levels and the knowledge to design appropriate solutions, in turn this will lead to more effective abatement. The continued monitoring allows the impact to be quantified giving confidence that intervention measures are worthwhile, delivering added value compared to current measurement methods

Ad hoc Acoustic Network Aided Localization for micro-AUVs

The navigation of Autonomous Underwater Vehicles (AUVs) is still an open research problem. This is further exacerbated when vehicles can only carry limited sensors as typically the case with micro-AUVs that need to survey large marine areas that can be characterized by high currents and dynamic environments. To address this problem, this work investigates the usage of ad hoc acoustic networks that can be established by a set of cooperating vehicles. Leveraging the network structure makes it possible to greatly improve the navigation of the vehicles and as a result to enlarge the operational envelope of vehicles with limited capabilities. The paper details the design and implementation of the network, and specific details of localization and navigation services made available to the vehicles by the network stack. Results are provided from a sea-trial undertaken in Croatia in October 2019. Results validate the approach, demonstrating the increased flexibility of the system and the navigational performance obtained: the deployed network was able to support long-range navigation of vehicles with no inertial navigation or Doppler Velocity Log (DVL) during a 9.5 km channel crossing, reducing the navigation error from approximately 7% to 0.27% of the distance traveled

Ultra-low-cost and ultra-low-power, miniature acoustic modems using multipath tolerant spread-spectrum techniques

To enable long-term, large-scale, dense underwater sensor networks or Internet of Underwater Things (IoUT) this research investigates new novel waveforms and experimental prototypes for robust communications on ultra-low-cost and ultra-low-power, miniature acoustic modems. Spread-spectrum M-ary orthogonal signalling (MOS) is used with symbols constructed from subsequences of long pseudorandom codes. This decorrelates multipath signals, even when the time-spread spans many symbols, so they present as random noise. A highly cost-engineered and miniaturised prototype acoustic modem implementation was created, for the 24 kHz–32 kHz band, with low receive power consumption (12.5 mW) and transmit power of 3 km in lakes and >2 km in the sea including severe multipath. In lake testing of a 7-node, multi-hop, sensor network with TDA-MAC protocol, packet delivery was near 100% for all nodes. Trials of acoustic sensor nodes in the North Sea achieved 99.5% data delivery over a 3-month period and a wide range of sea conditions. Modulation and hardware have proven reliable in a variety of underwater environments. Competitive range and throughput with low cost and power are attractive for large-scale and long-term battery-operated networks. This research has delivered a viable and affordable communication technology for future IoUT applications