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Longmore, S.

Publications and source records attributed to Longmore, S..

2 recordsLinked to original sources

Comparison of a computer vision model to a human observer in detecting African mammals in camera trap images within a safari park

Remote monitoring technologies are increasingly utilized in animal research for their capacity to enhance data collection efficiency. However, they present challenges, and as such researchers have resorted to utilizing deep learning to automatically classify acquired data therefore expediting the review process. While this practice is common in field studies it has been less adopted in zoo monitoring. In this paper we deploy the YOLOv10x model to monitor four species at Knowsley Safari in the UK: African lions (Panthera leo), Southern white rhino (Ceratotherium simum simum), Grevys zebra (Equus grevyi) and Olive baboons (Papio anubis). Camera trap images were processed and classified using the Conservation AI desktop application. The raw images were saved to facilitate the comparative analysis of the models predictions against the findings of human observed images. Processing time for both methods was compared using a subset of 3015 images with Conservation AI, reducing the time required to classify the images by 82% compared to a human analyst. Confusion matrix results showed high accuracy rates for all four species (>0.90). Analysis of count data showed significant differences in three species, where the human observer recorded more observations of each than Conservation AI (lion, rhino, baboon p<0.005). However, no significant difference was seen in zebra (p>0.05). A strong positive correlation in count data between both methodologies was seen in all species; baboon (rho=0.955, p<0.005), lion (rho = 0.969, p<0.005), rhino (rho=0.887, p<0.005) and zebra (rho=0.843, p<0.005). This study highlights the potential for these technologies as a monitoring system in zoos.

animal behavior and cognition↗

Specialised RNA decay fine-tunes monogenic antigen expression in African trypanosomes

Antigenic variation is a sophisticated immune evasion strategy employed by many pathogens. Trypanosoma brucei expresses a single Variant-Surface-Glycoprotein (VSG) from a large genetic repertoire, which they periodically switch throughout an infection. Co-transcribed with the active-VSG within a specialised nuclear body are expression-site-associated-genes (ESAGs), involved in important host-parasite interactions, including protecting the parasite from human serum lytic effects, modulating the hosts innate immune response and uptake of essential nutrients. Despite expression within the same polycistron, there is a significant differential expression between ESAGs and VSGs (>140-fold), however, the regulatory mechanism has remained elusive for decades. Here, using a combination of genetic tools, super resolution microscopy, proteomics and transcriptomics analyses, we identified three novel proteins, which are recruited in a hierarchical manner, forming discreet sub-nuclear condensates that are developmentally regulated and negatively regulate ESAG transcripts. Among them, Expression-Site-Body-specific-protein-2 (ESB2) contains a nuclease domain that shares structural similarity to the endonuclease domain found in SMG6, a critical component of nonsense mediated decay in mammals. Mutation of key residues required for the nuclease activity impaired ESB2 localisation and function. Overall, our findings reveal a novel mechanism of post-transcriptional regulation and shed light on how specialised RNA decay can regulate expression of specific genes.

molecular biology↗