2,034 research outputs found
Computer vision guidance for precise movement in commercial drones
A Thesis Submitted to the University of Bedfordshire, in Fulfilment of the Requirements for the Degree of Master of Sciences by ResearchThis project aims to pave the way for completely autonomous drone flight, starting
with using computer vision to guide a drone. The project will involve using computer
vision to direct a drone around a room to find its goal location. The current aims and
objectives are:
To implement computer control for drones and use this to run the program
through the drone;
To get the drone to recognize directions given by arrows using computer vision
and to translate arrows seen into lateral directions;
To accurately land the drone safely on or as close to a final goal position as
possible
‘An attempt to tip the scales’: music and embodied capital in an English secondary school
This article explores class, capital, and aspiration to social mobility in an ethnographic study of an English secondary school. In particular, the article considers the school’s musical instrument programme as a site for inculcating forms of capital, under the auspices of developing skills for upward social mobility. Bringing together Bourdieu’s conceptions of schooling with theories of materiality and situated learning, we contend that this school succeeds in cultivating new forms of embodied capital among students through the development of communities of musical practice. However, a tension remains between emancipatory aims of the programme and the sanctioning and championing of certain forms of dominant cultural practice. The learning environment of the instrument programme highlights the complex and conflicted impact that schooling can have on the development of cultural capital and on reproducing disadvantage and difference
Syndemics of stigma, minority-stress, maladaptive coping, risk environments and littoral spaces among men who have sex with men using chemsex
There has been a steep rise in the use of drugs during sex by some men who have sex with men in economically developed countries, with associated increases in sexual risk for HIV and other STIs. This paper presents data from telephone interviews with 15 men attending sexual health clinics for post-exposure prophylaxis (PEP) following a chemsex-related risk for HIV, and discusses some of the theoretical approaches that have been employed to understand chemsex and inform interventions. Interviews were conducted as part of a larger intervention study, which used an adapted version of motivational Interviewing to explore risk behaviour and support change. Participants conceptualised their chemsex and HIV-related risks in a psycho-social context, highlighting the influences of psycho-socio-cultural challenges of homophobic marginalisation and the ‘gay scene’ on behaviour. Multiple influences of stigma, marginalisation, minority stress and maladaptive coping (including drug-use) contribute to syndemic ‘risk-environments’ and ‘littoral spaces’ in which chemsex and risk behaviours are played out
Geometry of bend : singular lines and defects in twist-bend nematics
We describe the geometry of bend distortions in liquid crystals and their fundamental degeneracies, which we call β lines; these represent a new class of linelike topological defect in twist-bend nematics. We present constructions for smecticlike textures containing screw and edge dislocations and also for vortexlike structures of double twist and Skyrmions. We analyze their local geometry and global structure, showing that their intersection with any surface is twice the Skyrmion number. Finally, we demonstrate how arbitrary knots and links can be created and describe them in terms of merons, giving a geometric perspective on the fractionalization of Skyrmions
Global marine bacterial diversity peaks at high latitudes in winter.
Genomic approaches to characterizing bacterial communities are revealing significant differences in diversity and composition between environments. But bacterial distributions have not been mapped at a global scale. Although current community surveys are way too sparse to map global diversity patterns directly, there is now sufficient data to fit accurate models of how bacterial distributions vary across different environments and to make global scale maps from these models. We apply this approach to map the global distributions of bacteria in marine surface waters. Our spatially and temporally explicit predictions suggest that bacterial diversity peaks in temperate latitudes across the world's oceans. These global peaks are seasonal, occurring 6 months apart in the two hemispheres, in the boreal and austral winters. This pattern is quite different from the tropical, seasonally consistent diversity patterns observed for most macroorganisms. However, like other marine organisms, surface water bacteria are particularly diverse in regions of high human environmental impacts on the oceans. Our maps provide the first picture of bacterial distributions at a global scale and suggest important differences between the diversity patterns of bacteria compared with other organisms
The role of the North Atlantic Oscillation in controlling U.K. butterfly population size and phenology
Copyright @ 2012 The Authors. This article can be accessed from the links below.This article has been made available through the Brunel Open Access Publishing Fund.1. The North Atlantic Oscillation (NAO) exerts considerable control on U.K. weather. This study investigates the impact of the NAO on butterfly abundance and phenology using 34 years of data from the U.K. Butterfly Monitoring Scheme (UKBMS). 2. The study uses a multi-species indicator to show that the NAO does not affect overall U.K. butterfly population size. However, the abundance of bivoltine butterfly species, which have longer flight seasons, were found to be more likely to respond positively to the NAO compared with univoltine species, which show little or a negative response. 3. A positive winter NAO index is associated with warmer weather and earlier flight dates for Anthocharis cardamines (Lepidoptera: Pieridae), Melanargia galathea (Lepidoptera: Nymphalidae), Aphantopus hyperantus (Lepidoptera: Nymphalidae), Pyronia tithonus (Lepidoptera: Nymphalidae), Lasiommata megera (Lepidoptera: Nymphalidae) and Polyommatus icarus (Lepidoptera: Lycaenidae). In bivoltine species, the NAO affects the phenology of the first generation, the timing of which indirectly controls the timing of the second generation. 4. The NAO influences the timing of U.K. butterfly flight seasons more strongly than it influences population size.This study was supported by a multi-agency consortium led by the U.K. Department for Environment, Food and Rural Affairs (Defra), including the Countryside Council for Wales, the Joint Nature Conservation Committee, the Forestry Commission, Natural England, the Natural Environment Research Council, the Northern Ireland Environment Agency and Scottish Natural Heritage. This article is made available through the Brunel Open Access Publishing Fund
Finite group actions on reductive groups and buildings and tamely-ramified descent in Bruhat-Tits theory
The purpose of the paper is to give a new approach to tamely-ramified descent
in Bruhat-Tits theory. This descent was first studied by Guy Rousseau in his
thesis.Comment: 28 pages. arXiv admin note: text overlap with arXiv:1611.0743
Identifying genetic networks underlying myometrial transition to labor
BACKGROUND: Early transition to labor remains a major cause of infant mortality, yet the causes are largely unknown. Although several marker genes have been identified, little is known about the underlying global gene expression patterns and pathways that orchestrate these striking changes. RESULTS: We performed a detailed time-course study of over 9,000 genes in mouse myometrium at defined physiological states: non-pregnant, mid-gestation, late gestation, and postpartum. This dataset allowed us to identify distinct patterns of gene expression that correspond to phases of myometrial 'quiescence', 'term activation', and 'postpartum involution'. Using recently developed functional mapping tools (HOPACH (hierarchical ordered partitioning and collapsing hybrid) and GenMAPP 2.0), we have identified new potential transcriptional regulatory gene networks mediating the transition from quiescence to term activation. CONCLUSIONS: These results implicate the myometrium as an essential regulator of endocrine hormone (cortisol and progesterone synthesis) and signaling pathways (cyclic AMP and cyclic GMP stimulation) that direct quiescence via the transcripitional upregulation of both novel and previously associated regulators. With term activation, we observe the upregulation of cytoskeletal remodeling mediators (intermediate filaments), cell junctions, transcriptional regulators, and the coordinate downregulation of negative control checkpoints of smooth muscle contractile signaling. This analysis provides new evidence of multiple parallel mechanisms of uterine contractile regulation and presents new putative targets for regulating myometrial transformation and contraction
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