858 research outputs found
Longitudinal Match Performance Characteristics of UK and Non-UK Players in the English Premier League
This study investigated the longitudinal match performance characteristics in the English Premier League (EPL), with special reference to player nationality (UK vs. non-UK). Match observations (n = 14700) were collected using a multi-camera computerised tracking system across 7 consecutive EPL seasons (2006–2007 to 2012– 2013). Player nationality referred to their birthplace, with players born in England, Scotland, Wales or Northern Ireland classified as the UK players and other nationalities considered non-UK. The non-UK players demon- strated the most pronounced increases in high-intensity running distance across the 7 seasons compared with UK players (P 0.05, ES: 0.08 [CI 0.01–0.15]). In contrast, the non-UK players performed more passes in 2006–2007 compared with the UK players (P 0.05, ES: 0.05 [CI −0.01–0.13]). The data demonstrates that the longitudinal match performance characteristics in the EPL are similar between the UK and non-UK populations
Evolution of match performance parameters for various playing positions in the English Premier League
This study aimed to investigate position-specific evolution of physical and technical performance parameters in the English Premier League (EPL). Match performance observations (n = 14700) were collected using a multiple-camera computerized tracking system across seven seasons (2006–07 to 2012–13). Data were analyzed relative to five playing positions: central defenders (n = 3792), full backs (n = 3420), central midfielders (n = 3200), wide midfielders (n = 2136) and attackers (n = 2152). High-intensity running distance increased in the final season versus the first season in all playing positions (p < .05, ES: 0.9–1.3) with full backs displaying the greatest increase (∼36% higher in 2012–13). Similar trends were observed for sprint distance with full backs demonstrating the most pronounced increase across the seven seasons (36–63%, p < .001, ES: 0.8–1.3). Central players (central defenders and midfielders) illustrated the most pronounced increases in total passes and pass success rate (p < .05, ES: 0.7–0.9) whilst wide players (full backs and wide midfielders) demonstrated only small-moderate increases in total passes and pass success rate (p < .05, ES: 0.6–0.8). The data demonstrates that evolving tactics in the EPL have impacted on the physical demands of wide players and the technical requirements of central players. These findings could be used for talent identification or position-specific physical and technical training
Engineered acetoacetate-inducible whole-cell biosensors based on the AtoSC two-component system
Whole-cell biosensors hold potential in a variety of industrial, medical and environmental applications. These biosensors can be constructed through the repurposing of bacterial sensing mechanisms, including the common two-component system. Here we report on the construction of a range of novel biosensors that are sensitive to acetoacetate, a molecule that plays a number of roles in human health and biology. These biosensors are based on the AtoSC two-component system. An ordinary differential equation model to describe the action of the AtoSC two-component system was developed and sensitivity analysis of this model used to help inform biosensor design. The final collection of biosensors constructed displayed a range of switching behaviours, at physiologically relevant acetoacetate concentrations and can operate in several Escherichia coli host strains. It is envisaged that these biosensor strains will offer an alternative to currently available commercial strip tests and, in future, may be adopted for more complex in vivo or industrial monitoring applications
Modelling farmer decision-making to anticipate tradeoffs between provisioning ecosystem services and biodiversity
Anomaly/Transport in an Ideal Weyl gas
We study some of the transport processes which are specific to an ideal gas
of relativistic Weyl fermions and relate the corresponding transport
coefficients to various anomaly coefficients of the system. We propose that
these transport processes can be thought of as arising from the continuous
injection of chiral states and their subsequent adiabatic flow driven by
vorticity. This in turn leads to an elegant expression relating the anomaly
induced transport coefficients to the anomaly polynomial of the Ideal Weyl gas.Comment: 35 pages, JHEP forma
Holography for chiral scale-invariant models
Deformation of any d-dimensional conformal field theory by a constant null
source for a vector operator of dimension (d + z -1) is exactly marginal with
respect to anisotropic scale invariance, of dynamical exponent z. The
holographic duals to such deformations are AdS plane waves, with z=2 being the
Schrodinger geometry. In this paper we explore holography for such chiral
scale-invariant models. The special case of z=0 can be realized with gravity
coupled to a scalar, and is of particular interest since it is related to a
Lifshitz theory with dynamical exponent two upon dimensional reduction. We show
however that the corresponding reduction of the dual field theory is along a
null circle, and thus the Lifshitz theory arises upon discrete light cone
quantization of an anisotropic scale invariant field theory.Comment: 62 pages; v2, published version, minor improvements and references
adde
On Holographic description of the Kerr-Newman-AdS-dS black holes
In this paper, we study the holographic description of the generic
four-dimensional non-extremal Kerr-Newman-AdS-dS black holes. We find that if
focusing on the near-horizon region, for the massless scalar scattering in the
low-frequency limit, there exists hidden conformal symmetry on the solution
space. Similar to the Kerr case, this suggests that the Kerr-Newman-AdS-dS
black hole is dual to a two-dimensional CFT with central charges
and temperatures
. The macroscopic Bekenstein-Hawking
entropy could be recovered from the microscopic counting in dual CFT via the
Cardy formula. Using the Minkowski prescription, we compute the real-time
correlators of the scalar, photon and graviton in near horizon geometry of near
extremal Kerr-AdS-dS black hole. In all these cases, the retarded Green's
function and the corresponding absorption cross section are in perfect match
with CFT prediction. We further discuss the low-frequency scattering of a
charged scalar by a Kerr-Newman-AdS-dS black hole and find the dual CFT
description.Comment: 22 pages; minor corrections, conlusion unchanged, references
added;published versio
Schr\"odinger Holography with and without Hyperscaling Violation
We study the properties of the Schr\"odinger-type non-relativistic holography
for general dynamical exponent z with and without hyperscaling violation
exponent \theta. The scalar correlation function has a more general form due to
general z as well as the presence of \theta, whose effects also modify the
scaling dimension of the scalar operator. We propose a prescription for minimal
surfaces of this "codimension 2 holography," and demonstrate the (d-1)
dimensional area law for the entanglement entropy from (d+3) dimensional
Schr\"odinger backgrounds. Surprisingly, the area law is violated for d+1 < z <
d+2, even without hyperscaling violation, which interpolates between the
logarithmic violation and extensive volume dependence of entanglement entropy.
Similar violations are also found in the presence of the hyperscaling
violation. Their dual field theories are expected to have novel phases for the
parameter range, including Fermi surface. We also analyze string theory
embeddings using non-relativistic branes.Comment: 62 pages and 6 figures, v2: several typos in section 5 corrected,
references added, v3: typos corrected, references added, published versio
4-point correlators in finite-temperature AdS/CFT: jet quenching correlations
There has been recent progress on computing real-time equilibrium 3-point
functions in finite-temperature strongly-coupled N=4 super Yang-Mills (SYM). In
this paper, we show an example of how to carry out a similar analysis for a
4-point function. We look at the stopping of high-energy "jets" in such
strongly-coupled plasmas and relate the question of whether, on an
event-by-event basis, each jet deposits its net charge over a narrow (~ 1/T) or
wide (>> 1/T) spatial region. We relate this question to the calculation of a
4-point equilibrium correlator.Comment: 41 pages, 20 figures [change from v2: just a handful of minor grammar
corrections
Hidden Conformal Symmetry of Extremal Kerr-Bolt Spacetimes
We show that extremal Kerr-Bolt spacetimes have a hidden conformal symmetry.
In this regard, we consider the wave equation of a massless scalar field
propagating in extremal Kerr-Bolt spacetimes and find in the "near region", the
wave equation in extremal limit can be written in terms of the
quadratic Casimir. Moreover, we obtain the microscopic entropy of the extremal
Kerr-Bolt spacetimes also we calculate the correlation function of a
near-region scalar field and find perfect agreement with the dual 2D CFT.Comment: 13 page
- …