The red seaweed Asparagopsis taxiformis embodies five cryptic mitochondrial lineages (lineage 1-5) introduced worldwide as a consequence of human mediated transport and climate change. We compared globally collected mitochondrial cox2-3 intergenic spacer sequences with sequences produced from multiple Australian locations and South Korea to identify Asparagopsis lineages and to reveal cryptic introductions. We report A. taxiformis lineage 4 from Cocos (Keeling) Islands, Australia, and the highly invasive Indo-Pacific Mediterranean lineage 2 from South Korea and Lord Howe Island, Australia. Phylogeographic analysis showed a clear haplotype and geographic separation between western Australian and Great Barrier Reef (GBR) isolates belonging to the recently described lineage 5. The same lineage, however, was characterized by a substantial genetic and geographic break between the majority of Australian specimens and Asparagopsis collections from South Solitary Island, Southern GBR, Lord Howe Island, Kermadec Islands, Norfolk Island, New Caledonia and French Polynesia. The disjunct geographic distribution and sequence divergence between these two groups supports the recognition of a sixth cryptic A. taxiformis mitochondrial lineage. As climatic changes accelerate the relocation of biota and offer novel niches for colonization, periodic surveys for early detection of cryptic invasive seaweeds will be critical in determining whether eradication or effective containment of the aliens are feasible.
Novel tools and methods for monitoring marine environments can improve efficiency but must not compromise long-term data records. Quantitative comparisons between new and existing methods are therefore required to assess their compatibility for monitoring. Monitoring of shallow water coral reefs is typically conducted using diver-based collection of benthic images along transects. Diverless systems for obtaining underwater images (e.g. towed-cameras, remotely operated vehicles, autonomous underwater vehicles) are increasingly used for mapping coral reefs. Of these imaging platforms, towed-cameras offer a practical, low cost and efficient method for surveys but their utility for repeated measures in monitoring studies has not been tested. We quantitatively compare a towed-camera approach to repeated surveys of shallow water coral reef benthic assemblages on fixed transects, relative to benchmark data from diver photo-transects. Differences in the percent cover detected by the two methods was partly explained by differences in the morphology of benthic groups. The reef habitat and physical descriptors of the site—slope, depth and structural complexity—also influenced the comparability of data, with differences between the tow-camera and the diver data increasing with structural complexity and slope. Differences between the methods decreased when a greater number of images were collected per tow-camera transect. We attribute lower image quality (variable perspective, exposure and focal distance) and lower spatial accuracy and precision of the towed-camera transects as the key reasons for differences in the data from the two methods and suggest changes to the sampling design to improve the application of tow-cameras to monitoring.
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Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies to enable the Department of Defense (DoD) to meet its increasing requirements for access to the electromagnetic spectrum. A key open issue surrounding deployment and continuing development of DSA systems concerns (1) the need to test and evaluate the performance of DSA in avoiding interference to itself and assigned incumbent users and (2) the performance of DSA network in the presence of various types of potential interference. In this paper we describe test framework and concepts to characterize performance of DSA-enabled policy-based radios. Our test framework includes tests to characterize the inherent interference-avoidance characteristics of DSA, such as the time to abandon a channel, as well as tests that address performance implications of a particular DSA policy. The test framework also provides for the ability to inject a relevant electromagnetic environment (EME). The proposed framework is flexible allowing for customization of the relevant test conditions, such as the EME, and facilitates simulation of typical communications events such as network formation and fragmentation.
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The focus of this chapter is the renal system and the clinical skills that are associated with renal dysfunction. By the end of this chapter you will be knowledgeable in relation to these skills and your new knowledge will be underpinned by up-to-date evidence-based best practice. It is anticipated that you will be able to do the following once you have read and studied this chapter: ● Understand urine sampling techniques and urine testing methods and their significance in clinical practice. ● Understand the various procedures and investigations that the infant, child, or young person may have to endure for renal system evaluation. The urinary system is important in maintaining the correct water and electrolyte concentrations in the body. Waste products and excess water and ions are eliminated from the body in the urine. The kidneys are situated on either side of the vertebral column in the abdomen. The ureter, renal blood vessels, nerves, and lymphatics enter the kidney at a cleft on the medial side called the hilum. The adrenal gland lies on top of the kidney. The outside of each kidney is lined by: ● The renal capsule—a layer of collagen fibres. ● The adipose capsule—a layer of fat. ● The renal fascia—a layer of dense connective tissue. These three layers of tissue protect and support the kidney. The inside of each kidney contains an outer area (the cortex) and an inner area (the medulla). The cortex is lighter in colour compared to the dark reddish-brown medulla. The medulla contains cone-shaped areas of tissue called the medullary pyramids, which point towards the hilum. The cortex extends in between the medullary pyramids forming the renal columns. Urine forms at the tip of the pyramids (papillae) and drains into the minor calyx, then into a larger major calyx. Two or three major calyces join together to form the renal pelvis, a funnel-shaped chamber that leads into the ureter. Nephrons are the functional units of the kidney, the structures where urine is formed.
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