438 research outputs found

    Satellite monitoring of sea surface pollution

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    The author has identified the following significant results. Image processing techniques developed are well adapted to the exploration and isolation of local areas which exhibit small temperature differences between themselves and their surroundings. In the worst case of imagery of small areal extent of sea surface having no coastal boundary in the area, there is yet no method of distinguishing unambiguously an oil spill from fog, cloud, the effect produced by shallow sediments, or the effects of naturally occuring thermal fronts. In the case of uniform slicks of liquid North Sea oil in still air, laboratory simulation experiments show that, for oil thicknesses in excess of 1 or 2 mm, there is, under equilibrium conditions, little dependence of oil surface temperature on the thickness of the oil layer. The surface temperature of oil is consistently higher than that of water, the difference being about 1 K at low values of relative humidity, but tending to increase as the relative humidity increases

    Satellite monitoring of sea surface pollution

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    There are no author-identified significant results in this report

    Detect-alert-deter system for enhanced biosecurity and risk assessment

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    This project developed a prototype of a machine vision-based surveillance system to enhance wildlife biosecurity by automatically detecting and deterring target wildlife. It was programmed to recognise and target ducks, which are avian influenza (AI) reservoirs and a potential biosecurity risk. Other species may also be reservoir or bridge species that spread AI, and therefore seasonal surveys of wild birds on and around meat chicken farms were undertaken as wild bird migration patterns vary for wild birds at different times of the year

    Information Security as Strategic (In)effectivity

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    Security of information flow is commonly understood as preventing any information leakage, regardless of how grave or harmless consequences the leakage can have. In this work, we suggest that information security is not a goal in itself, but rather a means of preventing potential attackers from compromising the correct behavior of the system. To formalize this, we first show how two information flows can be compared by looking at the adversary's ability to harm the system. Then, we propose that the information flow in a system is effectively information-secure if it does not allow for more harm than its idealized variant based on the classical notion of noninterference

    Complete Sequence of pSAM7, an IncX4 Plasmid Carrying a Novel bla[sub]CTX-M-14b Transposition Unit Isolated from ' Escherichia coli ' and ' Enterobacter cloacae ' from cattle

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    The same plasmid carrying blaCTX-M-14b was identified from an Escherichia coli isolate and an Enterobacter cloacae isolate collected from cattle in the United Kingdom by complete plasmid sequencing. This 35,341-bp plasmid, pSAM7, had an IncX4 backbone that is 99% identical to that of pJIE143 from a human isolate in Australia. PCR screening identified pSAM7-like plasmids in three other E. coli isolates of different multilocus sequence types isolated from cattle on different farms in the United Kingdom

    The Prevalence of Spent Lead Shot in Wetland Sediments and Ingested by Wild Ducks in Coastal Queensland

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    Ingestion of spent lead shot by waterfowl, leading to lead poisoning, has been recorded in many parts of the world. In Australia, most attention has been in the southern states where hunting is more popular than elsewhere, and the assumption has been that, except for a few places, the prevalence of lead poisoning is low. To test this assumption, we collected digestive tracts of ducks from four localities and sediments from two wetlands in coastal Queensland where hunting occurs, but where there has been no suggestion that large numbers of birds may be exposed to the possibility of ingesting lead. We found a high prevalence of lead shot in the gut and sediment samples, suggesting that large numbers of birds may be at risk of lead poisoning, and that the prevalence is greater than the state prescribed threshold which would trigger a ban on the use of lead shot at some wetlands

    Emergency Management and Tourism Stakeholder Responses to Crises: A Global Survey

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    This paper examines the contested area of the responsibility for destinations and tourists, within emergency settings. It incorporates a Delphi-Scenario technique to facilitate a structured discussion of emergency management for different destination stakeholders. The Delphi exercise engaged 123 senior international stakeholders, from 9 different industry sectors, across 34 countries to provide a global perspective. The study’s principal focus is on the notion of emergency management, to identify the challenges that stakeholders would face within a disaster scenario. The exercise asked stakeholders to identify with whom the responsibility rests for 18 distinct disaster-related activities. The study proposes a responsibility allocation building-block framework which could help speed up the emergency management responses by ”knowing who is going to do what” with a particular focus on dealing with international tourists as a community in a disaster zone

    Spawning Habitat Unsuitability: An Impediment to Cisco Rehabilitation in Lake Michigan?

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    The cisco Coregonus artedi was one of the most important native prey fishes in Lake Michigan and in the other four Laurentian Great Lakes. Most of the cisco spawning in Lake Michigan was believed to have occurred in Green Bay. The cisco population in Lake Michigan collapsed during the 1950s, and the collapse was attributed in part to habitat degradation within Green Bay. Winter water quality surveys of lower Green Bay during the 1950s and 1960s indicated that the bottom dissolved oxygen (DO) concentration was less than 2 mg/L throughout much of the lower bay, and most cisco eggs would not successfully hatch at such low DO concentrations. To determine present‐day spawning habitat suitability in lower Green Bay, we compared cisco egg survival in lower Green Bay with survival at a reference site (St. Marys River, Michigan–Ontario) during 2009. We also conducted winter water quality surveys in lower Green Bay and the St. Marys River during 2009 and 2010. Cisco egg survival in lower Green Bay averaged 65.3%, which was remarkably similar to and not significantly different from the mean at the St. Marys River site (64.0%). Moreover, the lowest bottom DO concentrations recorded during the winter surveys were 11.2 mg/L in lower Green Bay and 12.7 mg/L in the St. Marys River. These relatively high DO concentrations would not be expected to have any negative effect on cisco egg survival. We conclude that winter water quality conditions in lower Green Bay were suitable for successful hatching of cisco eggs and that water quality during the egg incubation period did not represent an impediment to cisco rehabilitation in Lake Michigan. Our approach to determining spawning habitat suitability for coregonids would be applicable to other aquatic systems.Received May 14, 2011; accepted July 6, 2011Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142025/1/nafm0905.pd

    Factors influencing the consumption of seafood among young children in Perth: a qualitative study

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    <p>Abstract</p> <p>Background</p> <p>This formative study sought to explore the factors that influence the consumption of fish and seafood among 4–6 year old children in the Perth metropolitan area. Focus groups were conducted with mothers of young children to gain insights into the enablers and barriers to regular seafood consumption in children, and the knowledge, attitudes and perceptions of their mothers to including seafood as a regular part of their children's diet.</p> <p>Methods</p> <p>Purposive sampling techniques were used to select and recruit mothers of children aged between four and six years from within the Perth metropolitan area. A total of seven focus groups were conducted. Thematic content analysis was employed to code data generated and to extract major themes.</p> <p>Results</p> <p>Findings indicated that all children of study participants had tried fish and seafood products, with some being exposed to a wide variety from an early age. Across focus groups, several dominant factors were apparent in influencing the frequency and type of seafood purchased and consumed. Perceived cost, freshness, availability/accessibility, and the level of confidence to prepare a meal to suit all family members were significant determinants of whether seafood featured regularly on the household menu. The influence of others in the family (particularly the husband or partner) also tended to impact upon the likelihood of serving fish and seafood, and the types of products mothers were willing to serve.</p> <p>Conclusion</p> <p>Findings from this qualitative study indicate that interventions seeking to promote seafood (particularly fish) as an integral part of a healthy diet should address existing negative attitudes and beliefs around the storage and preparation of seafood. The influence of dominant male influences within the family unit should also be considered. Strategies directed at parents and children should include experimental 'hands-on' components to encourage experimentation, particularly focussing on ease of preparation and the variety of lower cost seafood available.</p

    VAST: An ASKAP Survey for Variables and Slow Transients

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    The Australian Square Kilometre Array Pathfinder (ASKAP) will give us an unprecedented opportunity to investigate the transient sky at radio wavelengths. In this paper we present VAST, an ASKAP survey for Variables and Slow Transients. VAST will exploit the wide-field survey capabilities of ASKAP to enable the discovery and investigation of variable and transient phenomena from the local to the cosmological, including flare stars, intermittent pulsars, X-ray binaries, magnetars, extreme scattering events, interstellar scintillation, radio supernovae and orphan afterglows of gamma ray bursts. In addition, it will allow us to probe unexplored regions of parameter space where new classes of transient sources may be detected. In this paper we review the known radio transient and variable populations and the current results from blind radio surveys. We outline a comprehensive program based on a multi-tiered survey strategy to characterise the radio transient sky through detection and monitoring of transient and variable sources on the ASKAP imaging timescales of five seconds and greater. We also present an analysis of the expected source populations that we will be able to detect with VAST.Comment: 29 pages, 8 figures. Submitted for publication in Pub. Astron. Soc. Australi
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