Examination of head versus body heading may help clarify the extent to which animal movement pathways are structured by environmental cues?

Understanding the processes that determine how animals allocate time to space is a major challenge, although it is acknowledged that summed animal movement pathways over time must define space-time use. The critical question is then, what processes structure these pathways? Following the idea that turns within pathways might be based on environmentally determined decisions, we equipped Arabian oryx with head- and body-mounted tags to determine how they orientated their heads – which we posit is indicative of them assessing the environment – in relation to their movement paths, to investigate the role of environment scanning in path tortuosity. After simulating predators to verify that oryx look directly at objects of interest, we recorded that, during routine movement, > 60% of all turns in the animals’ paths, before being executed, were preceded by a change in head heading that was not immediately mirrored by the body heading: The path turn angle (as indicated by the body heading) correlated with a prior change in head heading (with head heading being mirrored by subsequent turns in the path) twenty-one times more than when path turns occurred due to the animals adopting a body heading that went in the opposite direction to the change in head heading. Although we could not determine what the objects of interest were, and therefore the proposed reasons for turning, we suggest that this reflects the use of cephalic senses to detect advantageous environmental features (e.g. food) or to detect detrimental features (e.g. predators). The results of our pilot study suggest how turns might emerge in animal pathways and we propose that examination of points of inflection in highly resolved animal paths could represent decisions in landscapes and their examination could enhance our understanding of how animal pathways are structured

Near-field spectroscopy of colloidal quantum dots and vertical cavity surface emitting lasers.

A scanning near-field optical microscope (SNOM) has been employed for developments and measurements that allow spectroscopic characterisations on the nanoscale. To obtain spectral properties on spatial resolutions beyond the diffraction limit a spectrometer has been integrated into the SNOM system, together with various avalanche photodiode detectors, a cooled charge-coupled device and various filters, suitable to the experiments conducted. The system was optimised such that it allowed subsequent probe-positioning to perform point spectroscopy, using localised stimulation and collection techniques in the near-field. This spectral detection scheme has been applied to two areas of study, laser devices and quantum dot systems. The simultaneous topographical and optical study of semiconductor lasers, specifically vertical cavity surface emitting lasers (VCSEL), was carried out to spatially and spectrally map individual transverse mode emissions at the aperture surfaces in the nearfield. These measurements showed the clear presence of modulation of the intensity of the transverse modes in the form of concentric rings. The effect was attributed to a subsurface defect within the aperture of the device, clipping the Gaussian emission profile of the fundamental transverse mode. Higher order transverse modes were also found to be affected, revealing a more complex modulation structure due to their non-Gaussian emission. Structural defects, in or at the surface of such devices, have been shown to have significant effects on far-field characteristics. It is therefore important to spatially map the spectral source of such effects to gain insight into their origin. Spectral SNOM studies on quantum dots were conducted on mixed colour cadmium selenide/zinc sulphide (CdSe/ZnS), and cadmium selenide/hexadecylamine CdSe(HDA) quantum dots. Low concentrations were immobilised within a 2-3 nm thick layer of a PMMA polymer matrix, spin coated onto cleaved mica. Optical stimulation in the nearfield revealed simultaneous topographic and optical detection of single and small clusters of quantum dots. Spectroscopic measurements of single and small clusters of quantum dots in the near-field, showed a minimum spectral full width half maximum (FWHM) of ~14-16 nm. Repeated imaging of single quantum dots also showed fluorescence intermittency events on a range of time scales from below the time resolution of the set-up, to over an hour, in addition to fluorescence brightening. Conclusions as to the potential for quantum dots in biological imaging are discussed

Investigating the relationship between energy expenditure, walking speed and angle of turning in humans

Recent studies have suggested that changing direction is associated with significant additional energy expenditure. A failure to account for this additional energy expenditure of turning has significant implications in the design and interpretation of health interventions. The purpose of this study was therefore to investigate the influence of walking speed and angle, and their interaction, on energy expenditure in 20 healthy adults (7 female; 28±7 yrs). On two separate days, participants completed a turning protocol at one of 16 speed- (2.5, 3.5, 4.5, 5.5 km∙h-1) and angle (0, 45, 90, 180°) combinations, involving three minute bouts of walking, interspersed by three minutes seated rest. Each condition involved 5 m of straight walking before turning through the pre-determined angle with the speed dictated by a digital, auditory metronome. Tri-axial accelerometry and magnetometry were measured at 60 Hz, in addition to gas exchange on a breath-by-breath basis. Mixed models revealed a significant main effect for speed (F = 121.609, P < 0.001) and angle (F = 19.186, P < 0.001) on oxygen uptake () and a significant interaction between these parameters (F = 4.433, P < 0.001). Specifically, as speed increased, increased but significant increases in relative to straight line walking were only observed for 90° and 180° turns at the two highest speeds (4.5 and 5.5 km∙hr-1). These findings therefore highlight the importance of accounting for the quantity and magnitude of turns completed when estimating energy expenditure and have significant implications within both sport and health contexts

Citizens Apart? Representing post-Brexit youth politics in the UK media

In 2016, the UK voted to leave the European Union (EU). This outcome was not only unexpected but also had clear geographical and age-bound divisions. While people over the age of 65 tended to vote to leave, younger voters were more likely to vote to remain a part of the EU. Reflecting on 7 years of journalism, this paper explores the ways in which young people have been represented by the news media with regards to the issue of Brexit. It analyses a database of 700 news media articles published from 2016 to 2022 across the UK, equating to 100 articles per calendar year and ranging from regional sources to those with an international reach. The paper showcases how young people occupy liminal spaces within the news media through an analysis of the language used to describe their political participation, and a focus on their role within political activism. As it is this media that dominates hegemonic narratives within traditional political spheres, the retelling and representation of young people's engagement serves, we argue, to reinforce their liminality as citizens apart.</p

Keeping on[line] farming: Examining young farmers’ digital curation of identities, (dis)connection and strategies for self-care through social media

This paper explores the geographies of digital curation and self-care among young farmers in the UK, examining how virtual and digital spaces are having a significant impact on how young farmers negotiate their identities, (dis)connection and self-care within their everyday lives. Drawing on interviews with 28 young famers in the UK, we observe how farming identities are (re)produced and practiced online, via carefully curated social media, and how these might constitute practices of self-care in overcoming issues such as disconnection and rural isolation. Our analysis reveals how social media posts are more than simple connections, they are curations of the self that are complexly bound up in the emotional, spatial and temporal contexts of the author's identities. We examine how digital curation is not just an act of the self, but something drawn relationally to others. Attention is given not just to what is posted, but how others are (dis)engaged with, and how posts of others are reacted to, or endorsed, implicitly or explicitly. Through our examination of young farmers’ social identities, we therefore argue that digital identities are produced, practiced, managed and understood in very specific ways ‘online’, in ways that carefully overlap with other geographical identities

Animal lifestyle affects acceptable mass limits for attached tags

Animal-attached devices have transformed our understanding of vertebrate ecology. To minimize any associated harm, researchers have long advocated that tag masses should not exceed 3% of carrier body mass. However, this ignores tag forces resulting from animal movement. Using data from collar-attached accelerometers on 10 diverse free-ranging terrestrial species from koalas to cheetahs, we detail a tag-based acceleration method to clarify acceptable tag mass limits. We quantify animal athleticism in terms of fractions of animal movement time devoted to different collar-recorded accelerations and convert those accelerations to forces (acceleration x tag mass) to allow derivation of any defined force limits for specified fractions of any animal’s active time. Specifying that tags should exert forces <3% of the gravitational force exerted on the animal's body for 95% of the time led to corrected tag masses that should constitute between 1.6% and 2.98% of carrier mass, depending on athleticism. Strikingly, in four carnivore species encompassing two orders of magnitude in mass (ca. 2-200 kg), forces exerted by ‘3%’ tags were equivalent to 4-19% of carrier body mass during moving, with a maximum of 54% in a hunting cheetah. This fundamentally changes how acceptable tag mass limits should be determined by ethics bodies, irrespective of force and time limits specified

Belonging, pausing, feeling: a framework of “mobile dwelling” for U.K. university students that live at home

Notions of place and dwelling have become increasingly dynamic of late. No longer is place considered the sedentary equivalent to mobility, instead the spaces at which place and mobility intersect have produced exciting new ways of thinking about liminoid and mobile places, and how one might dwell in and through these intersections. In this paper we develop a framework of mobile dwelling to better understand student mobilities within UK higher education (HE), a sector that is framed by a set of binary dualisms – mobile/immobile, home/away, local/non-local. This dualistic thinking about im/mobility reflects the legacy of the “boarding school” model attached to traditional (and elite) HE participation, and newer permutations of undergraduate entry which is increasingly skewed towards the local. The framework developed here challenges these binary conceptualisations, which unhelpfully cast the growing number of live-at-home (LAH) students as immobile, writing out everyday movements such as commuting, and social and digital interactions with (and off) campus. Thus, by applying our concept of mobile dwelling to two UK-based studies, we reveal the complexities of LAH students’ daily mobilities; illuminating the pauses, the senses of belonging and the emotional reflections that are afforded by performances associated with commuting. By approaching everyday mobility as a tripartite experience of dwelling within/upon the liminoid spaces and experiences that constitute HE, we provide tools for understanding how marginal students make sense of their own identities, relationally understood against more traditional notions of studenthood

Highlighting when animals expend excessive energy for travel using dynamic body acceleration

Travel represents a major cost for many animals so there should be selection pressure for it to be efficient – at minimum cost. However, animals sometimes exceed minimum travel costs for reasons that must be correspondingly important. We use Dynamic Body Acceleration (DBA), an acceleration-based metric, as a proxy for movement-based power, in tandem with vertical velocity (rate of change in depth) in a shark (Rhincodon typus) to derive the minimum estimated power required to swim at defined vertical velocities. We show how subtraction of measured DBA from the estimated minimum power for any given vertical velocity provides a “proxy for power above minimum” metric (PPAmin), highlighting when these animals travel above minimum power. We suggest that the adoption of this metric across species has value in identifying where and when animals are subject to compelling conditions that lead them to deviate from ostensibly judicious energy expenditure

Quantifying allo-grooming in wild chacma baboons (Papio ursinus) using tri-axial acceleration data and machine learning

Quantification of activity budgets is pivotal for understanding how animals respond to changes in their environment. Social grooming is a key activity that underpins various social processes with consequences for health and fitness. Traditional methods use direct (focal) observations to calculate grooming rates, providing systematic but sparse data. Accelerometers, in contrast, can quantify activity budgets continuously but have not been used to quantify social grooming. We test whether grooming can be accurately identified using machine learning (random forest model) trained on labelled acceleration data from wild chacma baboons (Papio ursinus). We successfully identified giving and receiving grooming with high precision (81% and 91%) and recall (87% and 79%). Giving grooming was associated with a distinct rhythmical signal along the surge axis. Receiving grooming had similar acceleration signals to resting, and thus was more difficult to assign. We applied our machine learning model to n = 680 collar data days from n = 12 baboons and found that grooming rates obtained from accelerometers were significantly and positively correlated with direct observation rates for giving but not receiving grooming. The ability to collect continuous grooming data in wild populations will allow researchers to re-examine and expand upon long-standing questions regarding the formation and function of grooming bonds