1,627 research outputs found
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Engaging women and girls in martial arts and combat sports: theoretical issues and their implications for practice
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Love Fighting Hate Violence manifesto
Love Fighting Hate Violence (LFHV) is a campaign aiming to raise awareness of the important moral difference between sport-based combat, and violence. It seeks to encourage practitioners and fans of martial arts and combat sports to reflect on this distinction, and to encourage various forms of anti-violence action within and through their different disciplines.
This manifesto aims to clarify some of the central ideas and objectives of LFHV. It outlines the reasoning behind the campaign, points to the general spirit of what we hope it can achieve, and also hints at some ways it could be put into practice
Scalable variational Gaussian process classification
Gaussian process classification is a popular method with a number of
appealing properties. We show how to scale the model within a variational
inducing point framework, outperforming the state of the art on benchmark
datasets. Importantly, the variational formulation can be exploited to allow
classification in problems with millions of data points, as we demonstrate in
experiments.JH was supported by a MRC fellowship, AM and ZG by EPSRC grant EP/I036575/1, and a Google Focussed Research award.This is the final version of the article. It was first available from JMLR via http://jmlr.org/proceedings/papers/v38/hensman15.pd
MCMC for variationally sparse Gaussian processes
Gaussian process (GP) models form a core part of probabilistic machine
learning. Considerable research effort has been made into attacking three
issues with GP models: how to compute efficiently when the number of data is
large; how to approximate the posterior when the likelihood is not Gaussian and
how to estimate covariance function parameter posteriors. This paper
simultaneously addresses these, using a variational approximation to the
posterior which is sparse in support of the function but otherwise free-form.
The result is a Hybrid Monte-Carlo sampling scheme which allows for a
non-Gaussian approximation over the function values and covariance parameters
simultaneously, with efficient computations based on inducing-point sparse GPs.
Code to replicate each experiment in this paper will be available shortly.JH was funded by an MRC fellowship, AM and ZG by EPSRC grant EP/I036575/1 and a Google Focussed Research award.This is the final version of the article. It first appeared from the Neural Information Processing Systems Foundation via https://papers.nips.cc/paper/5875-mcmc-for-variationally-sparse-gaussian-processe
The JCMT Gould Belt Survey: the effect of molecular contamination in SCUBA-2 observations of Orion A
Thermal emission from cold dust grains in giant molecular clouds can be used
to probe the physical properties, such as density, temperature and emissivity
in star-forming regions. We present the SCUBA-2 shared-risk observations at 450
m and 850 m of the Orion A molecular cloud complex taken at the James
Clerk Maxwell Telescope (JCMT). Previous studies showed that molecular emission
lines can contribute significantly to the measured fluxes in those continuum
bands. We use the HARP CO J=3-2 integrated intensity map for Orion A in
order to evaluate the molecular line contamination and its effects on the
SCUBA-2 maps. With the corrected fluxes, we have obtained a new spectral index
map for the thermal emission of dust in the well-known integral-shaped
filament. Furthermore, we compare a sample of 33 sources, selected over the
Orion A molecular cloud complex for their high CO J=3-2 line
contamination, to 27 previously identified clumps in OMC-4. This allows us to
quantify the effect of line contamination on the ratio of 850 m to 450
m flux densities and how it modifies the deduced spectral index of
emissivity for the dust grains. We also show that at least one
Spitzer-identified protostellar core in OMC-5 has a CO J=3-2
contamination level of 16 %. Furthermore, we find the strongest contamination
level (44 %) towards a young star with disk near OMC-2. This work is part of
the JCMT Gould Belt Legacy Survey.Comment: 13 pages, 6 figures, Accepted for publication in Monthly Notices of
the Royal Astronomical Society (MNRAS
Post-fossilization processes and their implications for understanding Ediacaran macrofossil assemblages
Fossil assemblages from Newfoundland’s Avalon Peninsula preserve diverse examples of the enigmatic Ediacaran macrobiota, offering some of the earliest evidence for large and complex multicellular life. These fossils are exposed on extensive coastal bedding planes in extraordinary abundances, permitting palaeoecological studies based on census data from spatially extensive palaeocommunities. Such studies have been used to constrain the reproductive strategy and phylogenetic placement of Ediacaran organisms. Geological mapping and stratigraphic correlation in the Mistaken Point Ecological Reserve reveal that some fossil-bearing surfaces can be tracked over distances of several kilometres. These laterally extensive surfaces reveal that the modern processes by which the sediment overlying a fossil surface is removed may impose important controls on the observed composition of fossil assemblages. Weathering and erosion – along with factors associated with tectonics, metamorphism and discovery – are here grouped as ‘post-fossilization processes’ and introduce biases that are often not explicitly accounted for in palaeoecological studies. Specifically, post-fossilization processes may differentially influence the preservational fidelity of individual specimens on a given surface and generate features that could be mistaken for original morphological characters. We therefore recommend that post-fossilization processes must be considered when undertaking palaeoecological studies in Ediacaran successions in Newfoundland and, potentially, elsewhere.This research was supported by the Natural Environment Research Council [grant numbers NE/J5000045/1 to JJM, and NE/L011409/1 to AGL]. Joe Stewart and Tom Hearing are thanked for assistance in gathering field data. Thanks are also extended to Martin Brasier, without whom this research would never have taken place. Reviews from Matthew Clapham and one anonymous reviewer greatly improved the manuscript. The Parks and Natural Areas Division, Department of Environment and Conservation, Government of Newfoundland and Labrador, provided permits to conduct research within the Mistaken Point Ecological Reserve. Access to fossil localities within the Mistaken Point Ecological Reserve for research is by permit only. The fossils around Cape Race are protected by the Paleontological Resource Regulations 67/11, under the Historic Resources Act, 1990
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Sexualisation of the fighter's body: some reflections on women's mixed martial arts
This short paper offers an exploration of the ways in which a long-standing phenomenon in sport media portrayals of female athletes manifests in the newly-emerging field of women’s mixed martial arts (WMMA). Widely critiqued by scholars of sport media (e.g., Bruce, 2013; Kane, 2011), the sexual objectification of women in sport has long been held out as an example of the resilience of patriarchal logic within the world of sport. In brief, this argument rests on the notion that women’s entry into (specifically ‘masculine’) sports threatens orthodox gender hierarchies, because it provides women with opportunities to embody characteristics historically associated with men. Relative to discourses of gender which prioritise men’s ‘natural’ physical superiority, and take this as symbolic justification of men’s power elsewhere, female athleticism carries potentially radical connotations (Messner, 1988; Roth & Basow, 2004). However, sexualising female athletes undermines the challenge they might pose to dominant gender ideals, as it deflects attention away from the athletic capacities of women’s bodies whilst repositioning them as passive objects of the male gaze. Validating and rewarding female athletes on the basis of their heterosexual attractiveness reasserts hierarchal gender relations both within sport (sport is ‘by’ and ‘for’ heterosexual men), as well as without (women are only valuable when they become objects of men’s desire)
Do Children With Attention-Deficit/Hyperactivity Disorder Symptoms Become Socially Isolated? Longitudinal Within-Person Associations in a Nationally Representative Cohort.
OBJECTIVE: This study examined longitudinal associations between attention-deficit/hyperactivity disorder (ADHD) symptoms and social isolation across childhood. The study tested the direction of this association across time, while accounting for preexisting characteristics, and assessed whether this association varied by ADHD presentation, informant, sex, and socioeconomic status. METHOD: Participants included 2,232 children from the Environmental Risk (E-Risk) Longitudinal Twin Study. ADHD symptoms and social isolation were measured at ages 5, 7, 10, and 12. Random-intercept cross-lagged panel models were used to assess the directionality of the association across childhood. RESULTS: Children with increased ADHD symptoms were consistently at increased risk of becoming socially isolated later in childhood, over and above stable characteristics (β = .05-.08). These longitudinal associations were not bidirectional; isolated children were not at risk of worsening ADHD symptoms later on. Children with hyperactive ADHD presentation were more likely to become isolated, compared with inattentive presentation. This was evident in the school setting, as observed by teachers, but not by mothers at home. CONCLUSION: The study findings highlight the importance of enhancing peer social support and inclusion for children with ADHD, particularly in school settings. This study adds explanatory value beyond traditional longitudinal methods, as the results represent how individual children change over time, relative to their own preexisting characteristics. DIVERSITY & INCLUSION STATEMENT: We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented sexual and/or gender groups in science. We actively worked to promote sex and gender balance in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work
On-chip manipulation of single photons from a diamond defect
Operating reconfigurable quantum circuits with single photon sources is a key goal of photonic quantum information science and technology. We use an integrated waveguide device containing directional couplers and a reconfigurable thermal phase controller to manipulate single photons emitted from a chromium related color center in diamond. Observation of both a wavelike interference pattern and particlelike sub-Poissionian autocorrelation functions demonstrates coherent manipulation of single photons emitted from the chromium related center and verifies wave particle duality. © 2013 American Physical Society
The JCMT Gould Belt Survey: the effect of molecular contamination in SCUBA-2 observations of Orion A
JOURThis is the final version of the article. It was first published by Oxford Journals for the Royal Astronomical Society via http://dx.doi.org/ 10.1093/mnras/stv3009Thermal emission from cold dust grains in giant molecular clouds can be used to probe the physical properties, such as density, temperature and emissivity in star-forming regions. We present the Submillimetre Common-User Bolometer Array (SCUBA-2) shared-risk observations at 450 and 850 μm of the Orion A molecular cloud complex taken at the James Clerk Maxwell Telescope (JCMT). Previous studies showed that molecular emission lines can contribute significantly to the measured fluxes in those continuum bands. We use the Heterodyne Array Receiver Programme 12CO J = 3-2 integrated intensity map for Orion A in order to evaluate the molecular line contamination and its effects on the SCUBA-2 maps. With the corrected fluxes, we have obtained a new spectral index α map for the thermal emission of dust in the well-known integral-shaped filament. Furthermore, we compare a sample of 33 sources, selected over the Orion A molecular cloud complex for their high 12CO J = 3-2 line contamination, to 27 previously identified clumps in OMC 4. This allows us to quantify the effect of line contamination on the ratio of 850-450 μm flux densities and how it modifies the deduced spectral index of emissivity β for the dust grains. We also show that at least one Spitzer-identified protostellar core in OMC 5 has a 12CO J = 3-2 contamination level of 16 per cent. Furthermore, we find the strongest contamination level (44 per cent) towards a young star with disc near OMC 2. This work is part of the JCMT Gould Belt Legacy Survey
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