251 research outputs found
EvoIO: Community-driven standards for sustainable interoperability
Interoperability is the property that allows systems to work together independent of who created them, or how or for what purpose they were implemented. It is crucial for aggregating data from different online resources and for integrating different kinds of data. Interoperability is based on effective standards that become and remain broadly adopted. We argue that to develop and apply such standards for evolutionary and biodiversity data sustainably, we need a community-driven, open, and participatory approach. With the goal to build such an approach, the EvoIO collaboration emerged in 2009 from several NESCent-sponsored activities. EvoIO aims to be a nucleating center for developing, applying and disseminating interoperability technology that connects and coordinates between stakeholders, developers, and standards bodies.

Members of the EvoIO group have harnessed a variety of collaborative events to successfully build an initial stack of interoperability technologies that is owned by the community and open to participation. The stack addresses syntax, semantics, and programmable services, and at present includes the following components: NeXML (http://nexml.org), a NEXUS-inspired XML format that is validatable yet extensible; CDAO (http://www.evolutionaryontology.org), an ontology of comparative data analysis formalizing the semantics of evolutionary data and metadata; and PhyloWS (http://evoinfo.nescent.org/PhyloWS), a web- services interface standard for querying, retrieving, and referencing phylogenetic data on the web. Beyond demonstration prototypes, reference implementations of EvoIO stack technologies are starting to appear in production use. 

Aside from producing such information artefacts, EvoIO devotes much of its energy to applying principles of communication and organization that result in open and inclusive processes of community science. One of the key tools employed by EvoIO is the hackathon event format. Hackathons are highly collaborative, hands-on working meetings that catalyze practical innovation, train researchers, and foster cohesion as well as a sense of shared ownership in the results. In summary, we find that broad community participation, buy-in, and ownership are critical for developing interoperability in a sustainable fashion, and there are approaches and tools that can foster these effectively
Developing a ‘Clarity of Mind’: Exploring A Behaviour-Based Approach to Mental Toughness Development in International Youth Football
Mentally tough behaviours (MTbs) entail verbal or physical acts that allow athletes to engage their capacity to produce consistently high performances under pressure. However, researchers of mental toughness (MT) have typically focused on the characteristics that make an athlete mentally tough, rather than how these characteristics are developed through learning to, and reflecting on, the display of MTbs. Consequently, we explored the athlete MT development process within youth international football. Collaborating with a Union of European Football Associations (UEFA) National Association, age-group international players (n = 6), coaches (n = 6), support staff (n = 7), and parents (n = 6) were interviewed regarding MTbs, the specific contexts (e.g., training) that require MTbs, and how key personnel (e.g., coaches, parents, teammates) might help develop players’ MTbs in international youth football. Using thematic analysis, we found MT development to be a relational, multidimensional process, where players transacted with individuals (e.g., coaches) in their environment. These individuals’ behaviours (e.g., autonomy-supportive) influenced players’ propensity to engage in and reflect on contextually relevant MTbs, leading to MT understanding, development, and maintenance. We suggest organisations develop a common understanding of the MT development process and educate all relevant stakeholders regarding their role in supporting athletes to develop the capacity to perform consistently under pressure
Matter Distribution around Galaxies
We explore the mass distribution of material associated with galaxies from
the observation of gravitational weak lensing for the galaxy mass correlation
function with the aid of -body simulations of dark matter. The latter is
employed to unfold various contributions that contribute to the integrated line
of sight mass density. We conclude that galaxies have no definite edges of the
matter distribution, extending to the middle to neighbouring galaxies with the
density profile roughly beyond the virial radius. The mass
distributed beyond the virial radius (gravitationally bound radius) explains
the gap seen in the mass density estimates, the global value and typically from the luminosity density
multiplied by the mass to light ratio. We suggest to use a physical method of
gravitational lensing to characterise galaxy samples rather than characterise
them with photometric means.Comment: 16 pages, 5 figures. ApJ accepte
The Mean and Scatter of the Velocity Dispersion-Optical Richness Relation for maxBCG Galaxy Clusters
The distribution of galaxies in position and velocity around the centers of
galaxy clusters encodes important information about cluster mass and structure.
Using the maxBCG galaxy cluster catalog identified from imaging data obtained
in the Sloan Digital Sky Survey, we study the BCG-galaxy velocity correlation
function. By modeling its non-Gaussianity, we measure the mean and scatter in
velocity dispersion at fixed richness. The mean velocity dispersion increases
from 202+/-10 km/s for small groups to more than 854+/-102 km/s for large
clusters. We show the scatter to be at most 40.5+/-3.5%, declining to
14.9+/-9.4% in the richest bins. We test our methods in the C4 cluster catalog,
a spectroscopic cluster catalog produced from the Sloan Digital Sky Survey DR2
spectroscopic sample, and in mock galaxy catalogs constructed from N-body
simulations. Our methods are robust, measuring the scatter to well within
one-sigma of the true value, and the mean to within 10%, in the mock catalogs.
By convolving the scatter in velocity dispersion at fixed richness with the
observed richness space density function, we measure the velocity dispersion
function of the maxBCG galaxy clusters. Although velocity dispersion and
richness do not form a true mass-observable relation, the relationship between
velocity dispersion and mass is theoretically well characterized and has low
scatter. Thus our results provide a key link between theory and observations up
to the velocity bias between dark matter and galaxies.Comment: 25 pages, 15 figures, 2 tables, published in Ap
Cross-correlation Weak Lensing of SDSS galaxy Clusters II: Cluster Density Profiles and the Mass--Richness Relation
We interpret and model the statistical weak lensing measurements around
130,000 groups and clusters of galaxies in the Sloan Digital Sky Survey
presented by Sheldon et al. 2007 (Paper I). We present non-parametric
inversions of the 2D shear profiles to the mean 3D cluster density and mass
profiles in bins of both optical richness and cluster i-band luminosity. We
correct the inferred 3D profiles for systematic effects, including non-linear
shear and the fact that cluster halos are not all precisely centered on their
brightest galaxies. We also model the measured cluster shear profile as a sum
of contributions from the brightest central galaxy, the cluster dark matter
halo, and neighboring halos. We infer the relations between mean cluster virial
mass and optical richness and luminosity over two orders of magnitude in
cluster mass; the virial mass at fixed richness or luminosity is determined
with a precision of 13% including both statistical and systematic errors. We
also constrain the halo concentration parameter and halo bias as a function of
cluster mass; both are in good agreement with predictions of LCDM models. The
methods employed here will be applicable to deeper, wide-area optical surveys
that aim to constrain the nature of the dark energy, such as the Dark Energy
Survey, the Large Synoptic Survey Telescope and space-based surveys
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