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Modelling proxemic zone shapes from analytic and simulated motion strategies
No full textAutonomous robots need to navigate around and negotiate for space with humans. Proxemics is the study of zones of personal and social space which humans experience around themselves and others, and use to control spatial interactions. By formalizing proxemic zones, autonomous robots may interact similarly. This study shows how proxemic zones may be generated by kinetics and trust, with the social zone being the critical space in which a human must trust another agent to avoid collision under their possible future motions. Previous studies have formalized these kinematics but have assumed that zones are circular in shape and found only their radii. However the kinematics and trust concepts used to generate them enable models to take account of the heading and rotational kinematics involved. This is shown to result in new non-circular shapes for the proxemic zones, whose egg shapes match those which have been found empirically and assumed without prior theory by current practical robots. Numerical and approximate analytical solutions to describe the zone shapes and sizes are presented. Zones are shown to change shape and size in response to the properties of the other agent, and are shown to generalize to include the stopping distances taught to drivers and pedestrians as well as natural human body zones.</p
Building statistics proficiency for all learners through animations and the KitaaSTAT web-based statistics software
No full textThis slide is about the use of teacher-created, student-friendly web resources and the addition of visual elements to enhance student performance. </p
The effects of diet on the expression of male dimorphic colouration and weaponry in a species of neotropical katydid
No full textMale alternative reproductive tactics are taxonomically widespread, with many species showing males with distinctly different phenotypic characters such as body size or weaponry. Several mechanisms can drive the expression of these male morphs, including genetic polymorphism or environmental interactions during development. In insects, multiple male morphs are common in several Orders, including Coleoptera, Odonata and Hymenoptera, but are rare in Orthoptera. This study establishes the presence of two male phenotypic morphs in the bush cricket Satizabalus jorgevargasi, a species in which the males display mandibular weaponry, and tests the effects of diet on the expression of male dimorphic characters. Male nymphs were raised under standard conditions until adulthood whereupon morphological measurements were taken. Males raised under standard conditions showed two male phenotypes based on head size and body colouration – a major morph with larger heads and more colouration and a smaller and duller minor morph. A second group of male nymphs were housed individually and fed either a high protein diet or a high carbohydrate diet. Body weight and pronotum length were measured on a weekly basis as the nymphs developed, and once the males had matured, morphological and bioacoustics characters were measured. Diet had a significant impact on these male dimorphic characters with protein fed males having significantly larger heads, mandibles, and brighter colouration. Our data parallels that seen in other invertebrate groups, where higher levels of protein during maturation being key to the production of larger male morphs.</p
Spiritual Memory, Diasporic Justice: Recognising Aladura Churches as Living African Heritage
No full textAs more heritage institutions adopt the language of decolonisation, many forms of diasporic cultural expression—especially those rooted in non-Western spiritual traditions—remain invisible. Aladura churches in the UK, vibrant spaces of Yoruba ritual and cultural transmission—spaces of living African heritage—are entirely absent from frameworks like UNESCO’s Intangible Cultural Heritage (ICH) Convention (https://ich.unesco.org/en/convention). This piece draws on digital ethnographic research to argue that these churches are not just religious spaces—they are unrecognised heritage institutions.</p
Typography Theory Practice
No full textA lecture about the history and development of the Typewriter as part of a conference at Leeds Becket University, organised by Fraser Muggeridge.</p
Δ-Y transformations in manipulator’s stiffness analysis
No full textThe paper proposes a Δ-Y transformations technique for stiffness modelling of over-constrained manipulators with internal cross-linkages. It allows representing complex structures as a serial-parallel equivalent one that can be easily handled by the VJM-based method. To derive desired analytical expressions for the equivalent serial-parallel structure, the MSA-based stiffness modelling approach is employed first, which allows describing the stiffness response for both the Δ and Y structures operating with VJM-type stiffness matrices. Further, the desired relations between equivalent Δ-Y and Y-Δ stiffness matrices are obtained. The example of stiffness modelling of a non-rigid Gough-Stewart platform with multiple cross-linkages demonstrates the benefits of the proposed technique.</p
Hierarchical Training Improves Consistency of Pollen Classification on the Family Level
No full textAccurate classification of pollen grains is crucial in various fields such as biology, medicine, and environmental monitoring. Even though deep learning methods have improved performance over traditional hand-crafted approaches, existing models often do not take into account the taxonomic hierarchy information of pollen species. In this paper, we propose a hierarchical training framework that jointly optimizes at the family, genus, and species levels using a shared feature extractor and parallel classifier heads. We evaluate our methods using a newly created dataset of 1,787 microscopic pollen images from 274 species, belonging to 145 genera, or 47 families. Experimental results, using two different backbones, demonstrate that the hierarchical training setup improves consistency on the family level while maintaining comparable classification performance at the species level. These findings highlight the value of incorporating biological taxonomy into model training for fine-grained image classification tasks.</p
Comparative Analysis between Bayesian Model and Maximum Likelihood Model for Predicting End-Effector Position from Robot Kinematics
No full textIndustrial manipulators require high precision and accuracy to perform repetitive tasks without affecting the robotic platform and the different agents interacting in the operating environment. Therefore, the end-effector position is important for accurate task execution. Machine learning and statistical methods using kinematic models to estimate the end-effector position have significant limitations in accuracy, robustness, and generating capacity in the face of dynamic or unmodeled conditions. In this context, a comparative analysis between a Bayesian regression model and a maximum likelihood-based model is proposed to estimate the end-effector position from kinematic information of the manipulator, considering a priori knowledge about the effector positions and joint angles. Error metrics such as the mean square error, coefficient of determination, and generalization capacity in untrained trajectories are used to evaluate the performance of the models. The results disclosed that the maximum likelihood model exhibits greater computational efficiency under ideal conditions. In contrast, Bayesian models demonstrate a superior capacity to represent the uncertainty inherent in the kinematic model.</p
“The new DNP”: Discussion of the experimental ‘fat burner’ BAM15 on bodybuilding forums and YouTube
No full textBodybuilders are often at the forefront of experimental forms of drug use and the consumption of novel compounds. One form of enhancement drug use that has received increasing attention in recent years is weight-loss medicine use, including 2,4-dinitrophenol (DNP). However, the market for IPEDs is constantly evolving, with new drugs emerging in digital market spaces. This research focusses on discussions relating to one of these emerging drugs, BAM15, a weight-loss medicine that some bodybuilders perceive as a potentially safer but effective alternative to DNP. We explore the cultural contexts to the navigation of risk in relation to this emergent drug within digital bodybuilding cultures, applying a cultural theory of risk.The research is based on a netnography of forum threads and YouTube content. Thematic analysis was used to analyse discussions relating to BAM15 on two of the largest bodybuilding forums in the world, in addition to a YouTube instructional on the creation of BAM15 and its comment section.Our findings reveal that BAM15 is perceived as a promising, low-risk alternative to traditional weight-loss drugs like DNP. The video’s accessibility and step-by-step synthesis guide contributed to the normalisation of risk-taking behaviours. Comments from viewers indicated a high level of engagement, with many expressing intent to self-experiment with BAM15 despite limited clinical evidence. The study highlights the need for harm reduction frameworks to consider the cultural and digital dimensions of risk. We argue for more contextually informed, peer-led harm reduction interventions that address both material risks and cultural practices surrounding drug use.</p
A comparison of rapid weight loss practices within combat sport athletes subjected to <24 hour vs ≥24 hour competition weigh-ins
No full textThis study aimed to compare the rapid weight loss (RWL) practices of combat athletes (n = 35, male n = 30, female n = 5) from Great Britain subjected to <24 hour ‘<24h’ versus ≥24 hour ‘≥24h’ competition weigh-ins. The previously validated ‘Rapid Weight Loss Questionnaire’ established RWL practices. Of total responses, 31/35 (88.6 %) surveyed had reduced body mass to compete, (‘<24h’; 20 of 24, 83.3 %. ‘≥24h’; 11 of 11, 100 %). The ‘≥24h’ group attributed a significantly greater (p < 0.01) ‘habitual’ (9.7 % vs 5.2 %) and ‘highest’ (13.0 % vs 8.7 %) pre-competition body mass loss and post competition body mass gain (9.4 % vs 3.9 %) compared to ‘<24h’. The RWL score was significantly higher for the ‘≥24h’ group compared to the ‘<24h’ group (43.8 vs 28.2, p < 0.001). For the total cohort, ‘gradual dieting’ (61.3 %), ‘increased exercise (45.2 %), ‘restricting fluid ingestion’ (38.7 %) and ‘hot water immersion’ (32.3 %) were RWL methods most commonly ‘always’ used. Prevalence of RWL is high amongst competitive UK combat athletes and performed by all surveyed ≥24 h group athletes. Magnitude of RWL was significantly greater in ≥24 h group athletes, with athletes experiencing body mass loss levels (∼8–13 %) which are concerning from a health and performance perspective.</p