Current variability in the assessment of component position for the unhappy knee replacement.

INTRODUCTION: Total knee arthroplasty (TKA) has a success rate of 80-90%, but despite this encouraging figure a painful TKA can be a source of dismay for patients and surgeons. Computed tomography (CT) scan has been developed as a tool to collect data in the analysis of TKA component placement. Protocols used to collect such data exist in orthopaedic and radiology practice with little standardization and significant variation. The aim of this review article was to evaluate such variability by sampling a series of protocols from a range of different radiology practices within NSW, Australia in a case-based manner and to then compare them against any literature standards. METHODS: The literature was surveyed for existing CT scan protocols used in TKA assessment. These were then compared with a series of metropolitan and rural radiology firms across the public and private sectors in NSW, Australia. RESULTS: Considerable variability exists between current protocols across NSW, Australia, which differ with proposed literature standards. CONCLUSION: Variabilities encountered when comparing the different scanning protocols in use for the assessment of TKA constitute a large potential source of error in the analysis of TKA component positioning. The reliance surgeons place on such analyses suggests the need for an established scanning protocol with an incorporated grading system and standardized values to allow reproducible data to help assess and predict TKA function.

Termites mitigate the effects of drought in tropical rainforest.

Termites perform key ecological functions in tropical ecosystems, are strongly affected by variation in rainfall, and respond negatively to habitat disturbance. However, it is not known how the projected increase in frequency and severity of droughts in tropical rainforests will alter termite communities and the maintenance of ecosystem processes. Using a large-scale termite suppression experiment, we found that termite activity and abundance increased during drought in a Bornean forest. This increase resulted in accelerated litter decomposition, elevated soil moisture, greater soil nutrient heterogeneity, and higher seedling survival rates during the extreme El Niño drought of 2015-2016. Our work shows how an invertebrate group enhances ecosystem resistance to drought, providing evidence that the dual stressors of climate change and anthropogenic shifts in biotic communities will have various negative consequences for the maintenance of rainforest ecosystems.

Elevational sensitivity in an Asian 'hotspot': moth diversity across elevational gradients in tropical, sub-tropical and sub-alpine China.

South-western China is widely acknowledged as a biodiversity 'hotspot': there are high levels of diversity and endemism, and many environments are under significant anthropogenic threats not least climate warming. Here, we explore diversity and compare response patterns of moth assemblages among three elevational gradients established within different climatic bioregions - tropical rain forest, sub-tropical evergreen broad-leaved forest and sub-alpine coniferous forest in Yunnan Province, China. We hypothesised that tropical assemblages would be more elevationally stratified than temperate assemblages, and tropical species would be more elevationally restricted than those in the temperate zone. Contrary to our hypothesis, the moth fauna was more sensitive to elevational differences within the temperate transect, followed by sub-tropical and tropical transects. Moths in the cooler and more seasonal temperate sub-alpine gradient showed stronger elevation-decay beta diversity patterns, and more species were restricted to particular elevational ranges. Our study suggests that moth assemblages are under threat from future climate change and sub-alpine rather than tropical faunas may be the most sensitive to climate change. These results improve our understanding of China's biodiversity and can be used to monitor future changes to herbivore assemblages in a 'hotspot' of biodiversity.

A pilot study of three potential vaccines for leprosy in Bombay.

Three vaccines, BCG Glaxo alone (vaccine A), BCG Glaxo plus 10(7) killed Mycobacterium vaccae (vaccine B), and BCG Glaxo plus 10(7) killed M. leprae (vaccine C), were given to groups of selected children. The effects of these vaccines on subsequent quadruple skin testing 1-3 years after vaccination were compared. All three vaccines equally and significantly (p less than 0.00001) increased positivity to tuberculin, but only vaccine B was found to significantly enhance development of skin-test positivity to leprosin A (p less than 0.002). The data support the evidence previously obtained in rural Iran that the combination of BCG with killed M. vaccae is likely to be a better vaccine for leprosy than is BCG alone.