Validation of the aerodynamic loading on basic flying disc geometries derived from CFD simulations

The present study in spin stabilised disc aerodynamics builds on previous experimental wind tunnel work to broaden the knowledge base through CFD simulation without the necessity for high facility or time cost. The current experimental database from previous studies is extensive enough for sufficient validation to be conducted on known geometries. From there, the limitations of CFD studies for this application on such complex highly separated bluff body flows can be understood. All of the results are for non-spinning discs to reduce computational time, this step is justifiable as the spinning case has previously been shown to have minimal effect on the aerodynamic loads at typical throw release spin rates. The work builds CFD simulation cases carefully and systematically starting with cylindrical discs with thickness to chord (diameter) ratio of 0.01 and 0.1, then to introduce a cavity to one flat side analogous to the Frisbee disc, before moving to look at a generic discus geometry from field athletics. The aerodynamic loading results compare very well to experimental data for the low angle of attack range, however, at higher angles of attack the CFD curves are divergent. It is possible that the generated mesh, for each geometry, does not capture the wake with enough resolution at high angles of attack, note that for sports disc applications the high angle of attack range is very important towards the end of the flight from a human throw. Therefore, further investigations are required to extend this initial study to a modified meshing regime with further refinement, prior to moving forward with any parametric design studies. Keyword - Spin-stabilised; sports disc; discwing; gyroscopic; aerodynamics; cf

A Study into the Effect of Mobile Device Configurations on Co-Located Collaboration using AR

The increasing availability of portable handheld mobile Augmented Reality technology is revolutionising the way digital information is embedded into the real world. As this data is embedded, it enables new forms of cross-device collaborative work. However, despite the widespread availability of handheld AR, little is known about the role that device configurations and size play on collaboration. This paper presents a study that examines how completing tasks using a simple mobile AR interface on different device sizes and configurations impacts key factors of collaboration such as collaboration strategy, behaviour, and efficacy. Our results show subtle differences between device size and configurations that have a direct influence on the way people approach tasks and interact with virtual models. We highlight key observations and strategies that people employ across different device sizes and configurations

Radi-Eye:Hands-Free Radial Interfaces for 3D Interaction using Gaze-Activated Head-Crossing

Eye gaze and head movement are attractive for hands-free 3D interaction in head-mounted displays, but existing interfaces afford only limited control. Radi-Eye is a novel pop-up radial interface designed to maximise expressiveness with input from only the eyes and head. Radi-Eye provides widgets for discrete and continuous input and scales to support larger feature sets. Widgets can be selected with Look & Cross, using gaze for pre-selection followed by head-crossing as trigger and for manipulation. The technique leverages natural eye-head coordination where eye and head move at an offset unless explicitly brought into alignment, enabling interaction without risk of unintended input. We explore Radi-Eye in three augmented and virtual reality applications, and evaluate the effect of radial interface scale and orientation on performance with Look & Cross. The results show that Radi-Eye provides users with fast and accurate input while opening up a new design space for hands-free fluid interaction

Supporting local diversity of habitats and species on farmland: a comparison of three wildlife-friendly schemes

Restoration and maintenance of habitat diversity have been suggested as conservation priorities in farmed landscapes, but how this should be achieved and at what scale are unclear. This study makes a novel comparison of the effectiveness of three wildlife-friendly farming schemes for supporting local habitat diversity and species richness on 12 farms in England. The schemes were: (i) Conservation Grade (Conservation Grade: a prescriptive, non-organic, biodiversity-focused scheme), (ii) organic agriculture and (iii) a baseline of Entry Level Stewardship (Entry Level Stewardship: a flexible widespread government scheme). Conservation Grade farms supported a quarter higher habitat diversity at the 100-m radius scale compared to Entry Level Stewardship farms. Conservation Grade and organic farms both supported a fifth higher habitat diversity at the 250-m radius scale compared to Entry Level Stewardship farms. Habitat diversity at the 100-m and 250-m scales significantly predicted species richness of butterflies and plants. Habitat diversity at the 100-m scale also significantly predicted species richness of birds in winter and solitary bees. There were no significant relationships between habitat diversity and species richness for bumblebees or birds in summer. Butterfly species richness was significantly higher on organic farms (50% higher) and marginally higher on Conservation Grade farms (20% higher), compared with farms in Entry Level Stewardship. Organic farms supported significantly more plant species than Entry Level Stewardship farms (70% higher) but Conservation Grade farms did not (10% higher). There were no significant differences between the three schemes for species richness of bumblebees, solitary bees or birds. Policy implications. The wildlife-friendly farming schemes which included compulsory changes in management, Conservation Grade and organic, were more effective at increasing local habitat diversity and species richness compared with the less prescriptive Entry Level Stewardship scheme. We recommend that wildlife-friendly farming schemes should aim to enhance and maintain high local habitat diversity, through mechanisms such as option packages, where farmers are required to deliver a combination of several habitats

ZenG:AR neurofeedback for meditative mixed reality

In this paper we present ZenG, a neurofeedback ARapplication concept based on Zen Gardening to fostercreativity, self-awareness, and relaxation through embodiedinteractions in a mixed reality environment. We developedan initial prototype which combined physiological sensingthrough EEG with AR visualisation on the Magic LeapDisplay. We evaluated the prototype through preliminaryuser testing with 12 adults. Results suggest users found theexperience to be enjoyable and relaxing, however theapplication could be improved by including more featuresand functionality. ZenG shows the potential for AR toprovide immersive and interactive environments that couldpromote creativity and relaxation, providing solid groundsfor further research

Crop pests and predators exhibit inconsistent responses to surrounding landscape composition

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Exploring the Making, Modifying, and Use of Physical Tools in Augmented Reality

The relationship between humans and physical tools is fundamental to all forms of work. With the proliferation of technology, the field of Human-Computer Interaction has focussed on the development of tools to interface with computers. Augmented Reality (AR) is one such technology that has gained prominence in recent years by merging physical and digital elements to enhance labour and promising more versatile and adaptive forms of work. While virtual objects provided by AR can enrich our physical environments, they remain intangible, presenting a number of challenges and opportunities for interaction. Considering this, we first argue the necessity of adopting physical tools to interact with virtual objects in AR. Second, the design of physical tools in AR can yield entirely new interaction possibilities especially when combined with the physical environment. And third, we advocate for the use of physical but versatile tools in AR, capable of modification to meet the demands of the task and user. This thesis explores Tool-making, Tool-Modifying, and Tool-Using for interacting with virtual objects in head-mounted display AR. The research includes a design space of physically-modifiable AR tools, supported by two empirical studies, and a toolkit for creating physically-modifiable cubic AR tools. We outline the surface-based touch gestures and 3D interaction techniques enabled by the cubic tools and combine them into five demonstrative AR applications. Lastly, we empirically explore and evaluate a 3D manipulation technique enabled by the toolkit. Results of the design space exploration and studies showcase how physically-modifiable AR tools can engender novel forms of interaction, alleviate common limitations of physical interfaces, and address certain interaction challenges in current AR techniques. The aim of this thesis is to stimulate fresh considerations for AR design, bringing interaction to the physical environment where humans excel, and envisioning tools as the ultimate mediators in the ultimate display