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Seagrasses are considered indicators of anthropogenic impact but surprisingly little is known about their temporal and spatial dynamics in impacted seascapes. In this study, we used three decades of Landsat imagery (1988-2018) off the coast of Adelaide, South Australia, to investigate how seagrass cover over 501 km 2 responds to changes in land-based inputs, including breakpoints in system trajectory and associated timelags, and the identification of vulnerable meadows. Field data was used to help train benthic classification of summer imagery and define its accuracy. Temporal dynamics of seagrass cover were investigated in relation to annual and multi-year nitrogen and suspended solids loads. Spatial dynamics were inferred from maps of benthic cover persistence and trajectory for each decade. The region experienced a net regrowth of some 11,000 ha of seagrasses since the early 2000s, with the initial large-scale recruitment visible in the imagery 6 years after the closure of sludge outfalls. Seagrass expansion occurred primarily in deeper waters (>10 m) of the central coast and at the seaward edge of the distribution. Recovery continued until 2011 assisted by a window of opportunity created by a decade-long drought and further reductions in nitrogen loads from wastewater treatment plants and industry. Localized seagrass losses however continued to be observed as a result of either permanent or transient increases in suspended solids loads. Seagrass area in the central coast was well correlated (r 2  = 0.88) with 5-year running averages of nitrogen and suspended solids loads. Meadows particularly vulnerable to changes in land-based discharges were located at the edges of the distribution, along erosional scarps and at depths >10 m south of the Torrens River. These areas were identified as useful indicators of seagrass status. Overall, seagrass persistence expanded from 48 to 69% of the mapped area, with the region now mostly covered by stable seagrasses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Modern satellite imaging offers radical new insights of the challenges and opportunities confronting traditional Aboriginal ecology and land use in Australia's Western Desert. We model the likely dynamics of historic and precontact desert land use using Earth observation data to identify the distribution of suitable foraging habitats. Suitability was modelled for an ideal environmental scenario, based on satellite observations of maximal water abundance, vegetation greenness, and terrain ruggedness. Our model shows that the highest-ranked foraging habitats do not align with land systems or bioregions that have been used in previous reconstructions of Australian prehistory. We identify impoverished desert areas where unsuitable foraging conditions have likely persisted since early in the last glacial cycle, and in which occupation would always have been rare. These findings lead us to reconsider past patterns of land use and the predicted archaeological signature of earlier desert peoples.

This case report describes secondary pelvic bone involvement by an uncommon bone tumour. Adamantmoma of the jaw accounts for only one per cent of all tumours in this area, and although gland and lung involvement have been described, bone involvement is rare., Summary: The case of a patient with secondary bone involvement from adamantinoma of the maxilla is reported.

Acute spinal epidural abscess is described in two patients. In the patient in whom the abscess was recognized early and decompression effected a complete recovery of cord function occurred, whereas in the second case, where recognition and treatment were delayed, permanent damage was the end-result. Severe back pain with evidence of infection must be checked frequently for neurological evidence of deterioration., Summary: 1. Two cases of acute spinal epidural abscess are reported. 2. Complete recovery followed early drainage in one case. 3. Late diagnosis in the second case was attended by a poor result. 4. The development of severe pain in the back with signs of infection may merge almost imperceptibly with the onset of neurological signs and symptoms.

Nerve injuries are more common in the upper limb than in the lower. The principles governing repair, however, are the same., (Copyright © 1966 Australian Physiotherapy Association. Published by . All rights reserved.)