Representation of Instantaneous and Short-Term Loudness in the Human Cortex.

Acoustic signals pass through numerous transforms in the auditory system before perceptual attributes such as loudness and pitch are derived. However, relatively little is known as to exactly when these transformations happen, and where, cortically or sub-cortically, they occur. In an effort to examine this, we investigated the latencies and locations of cortical entrainment to two transforms predicted by a model of loudness perception for time-varying sounds: the transforms were instantaneous loudness and short-term loudness, where the latter is hypothesized to be derived from the former and therefore should occur later in time. Entrainment of cortical activity was estimated from electro- and magneto-encephalographic (EMEG) activity, recorded while healthy subjects listened to continuous speech. There was entrainment to instantaneous loudness bilaterally at 45, 100, and 165 ms, in Heschl's gyrus, dorsal lateral sulcus, and Heschl's gyrus, respectively. Entrainment to short-term loudness was found in both the dorsal lateral sulcus and superior temporal sulcus at 275 ms. These results suggest that short-term loudness is derived from instantaneous loudness, and that this derivation occurs after processing in sub-cortical structures.This work was supported by an ERC Advanced Grant (230570, ‘Neurolex’) to WMW, and by MRC Cognition and Brain Sciences Unit (CBU) funding to WMW (U.1055.04.002.00001.01). Computing resources were provided by the MRC-CBU.This is the final version of the article. It first appeared from Frontiers via http://dx.doi.org/10.3389/fnins.2016.0018

Tracking cortical entrainment in neural activity: auditory processes in human temporal cortex.

A primary objective for cognitive neuroscience is to identify how features of the sensory environment are encoded in neural activity. Current auditory models of loudness perception can be used to make detailed predictions about the neural activity of the cortex as an individual listens to speech. We used two such models (loudness-sones and loudness-phons), varying in their psychophysiological realism, to predict the instantaneous loudness contours produced by 480 isolated words. These two sets of 480 contours were used to search for electrophysiological evidence of loudness processing in whole-brain recordings of electro- and magneto-encephalographic (EMEG) activity, recorded while subjects listened to the words. The technique identified a bilateral sequence of loudness processes, predicted by the more realistic loudness-sones model, that begin in auditory cortex at ~80 ms and subsequently reappear, tracking progressively down the superior temporal sulcus (STS) at lags from 230 to 330 ms. The technique was then extended to search for regions sensitive to the fundamental frequency (F0) of the voiced parts of the speech. It identified a bilateral F0 process in auditory cortex at a lag of ~90 ms, which was not followed by activity in STS. The results suggest that loudness information is being used to guide the analysis of the speech stream as it proceeds beyond auditory cortex down STS toward the temporal pole.This work was supported by an EPSRC grant to William D. Marslen-Wilson and Paula Buttery (EP/F030061/1), an ERC Advanced Grant (Neurolex) to William D. Marslen-Wilson, and by MRC Cognition and Brain Sciences Unit (CBU) funding to William D. Marslen-Wilson (U.1055.04.002.00001.01). Computing resources were provided by the MRC-CBU and the University of Cambridge High Performance Computing Service (http://www.hpc.cam.ac.uk/). Andrew Liu and Phil Woodland helped with the HTK speech recogniser and Russell Thompson with the Matlab code. We thank Asaf Bachrach, Cai Wingfield, Isma Zulfiqar, Alex Woolgar, Jonathan Peelle, Li Su, Caroline Whiting, Olaf Hauk, Matt Davis, Niko Kriegeskorte, Paul Wright, Lorraine Tyler, Rhodri Cusack, Brian Moore, Brian Glasberg, Rik Henson, Howard Bowman, Hideki Kawahara, and Matti Stenroos for invaluable support and suggestions.This is the final published version. The article was originally published in Frontiers in Computational Neuroscience, 10 February 2015 | doi: 10.3389/fncom.2015.0000

Excavations and the afterlife of a professional football stadium, Peel Park, Accrington, Lancashire: towards an archaeology of football

Association football is now a multi-billion dollar global industry whose emergence spans the post-medieval to the modern world. With its professional roots in late 19th-century industrial Lancashire, stadiums built for the professionalization of football first appear in frequency in the North of England. While many historians of sport focus on consumerism and ‘topophilia’ (attachment to place) regarding these local football grounds, archaeological research that has been conducted on the spectator experience suggests status differentiation within them. Our excavations at Peel Park confirm this impression while also showing a significant afterlife to this stadium, particularly through children’s play

Twirling and Whirling: Viscous Dynamics of Rotating Elastica

Motivated by diverse phenomena in cellular biophysics, including bacterial flagellar motion and DNA transcription and replication, we study the overdamped nonlinear dynamics of a rotationally forced filament with twist and bend elasticity. Competition between twist injection, twist diffusion, and writhing instabilities is described by a novel pair of coupled PDEs for twist and bend evolution. Analytical and numerical methods elucidate the twist/bend coupling and reveal two dynamical regimes separated by a Hopf bifurcation: (i) diffusion-dominated axial rotation, or twirling, and (ii) steady-state crankshafting motion, or whirling. The consequences of these phenomena for self-propulsion are investigated, and experimental tests proposed.Comment: To be published in Physical Review Letter

A robust SNP barcode for typing Mycobacterium tuberculosis complex strains

Strain-specific genomic diversity in the Mycobacterium tuberculosis complex (MTBC) is an important factor in pathogenesis that may affect virulence, transmissibility, host response and emergence of drug resistance. Several systems have been proposed to classify MTBC strains into distinct lineages and families. Here, we investigate single-nucleotide polymorphisms (SNPs) as robust (stable) markers of genetic variation for phylogenetic analysis. We identify ~92k SNP across a global collection of 1,601 genomes. The SNP-based phylogeny is consistent with the gold-standard regions of difference (RD) classification system. Of the ~7k strain-specific SNPs identified, 62 markers are proposed to discriminate known circulating strains. This SNP-based barcode is the first to cover all main lineages, and classifies a greater number of sublineages than current alternatives. It may be used to classify clinical isolates to evaluate tools to control the disease, including therapeutics and vaccines whose effectiveness may vary by strain type

Pre-treatment cerebrospinal fluid bacterial load correlates with inflammatory response and predicts neurological events during tuberculous meningitis treatment.

Background Mycobacterium tuberculosis (Mtb) bacillary load in the brain of those with tuberculous meningitis (TBM) may reflect the host ability to control the pathogen and determine disease severity and treatment outcomes. Methods We measured pre-treatment cerebrospinal fluid (CSF) Mtb bacterial load by GeneXpert in 692 adults with TBM. We sought to understand the relationship between CSF bacterial load and inflammation, and their respective impact on disease severity and treatment outcomes. Results Ten-fold higher Mtb load was associated with increased disease severity (Odds Ratio=1.59, p=0.001 for grade 1 versus grade 3), and increased CSF neutrophils (r=0.364, p<0.0001) and cytokine concentrations (r=0.438, p<0.0001). High Mtb load predicted new neurological events after starting treatment (Multinomial logistic regression, p=0.005), but not death. Death was previously associated with attenuated inflammatory response at the start of treatment, with reduced cytokine concentrations compared to survivors. In contrast, patients with high pre-treatment CSF bacterial loads, cytokines, and neutrophils were more likely to subsequently suffer neurological events. Conclusions Pre-treatment GeneXpert-derived Mtb load may be a useful predictor of neurological complications occurring during TBM treatment. Therapeutic strategies aimed at reducing neurological complications and deaths from TBM may need reassessment, given the evidence for their divergent pathogenesis

The Viscous Nonlinear Dynamics of Twist and Writhe

Exploiting the "natural" frame of space curves, we formulate an intrinsic dynamics of twisted elastic filaments in viscous fluids. A pair of coupled nonlinear equations describing the temporal evolution of the filament's complex curvature and twist density embodies the dynamic interplay of twist and writhe. These are used to illustrate a novel nonlinear phenomenon: ``geometric untwisting" of open filaments, whereby twisting strains relax through a transient writhing instability without performing axial rotation. This may explain certain experimentally observed motions of fibers of the bacterium B. subtilis [N.H. Mendelson, et al., J. Bacteriol. 177, 7060 (1995)].Comment: 9 pages, 4 figure

UK Housing Market: Time Series Processes with Independent and Identically Distributed Residuals

The paper examines whether a univariate data generating process can be identified which explains the data by having residuals that are independent and identically distributed, as verified by the BDS test. The stationary first differenced natural log quarterly house price index is regressed, initially with a constant variance and then with a conditional variance. The only regression function that produces independent and identically distributed standardised residuals is a mean process based on a pure random walk format with Exponential GARCH in mean for the conditional variance. There is an indication of an asymmetric volatility feedback effect but higher frequency data is required to confirm this. There could be scope for forecasting the index but this is tempered by the reduction in the power of the BDS test if there is a non-linear conditional variance process

An experimental investigation of the boundary layer on a porous circular cylinder

The report describes an experimental investigation of the boundary laver on the surface of a porous circular cylinder at which there is a normal inward velocity. The primary object of the experiments was to test the approximate theory of Ref. 1 for calculating the development of a laminar boundary layer under conditions of continuous suction. The formula given in that reference for calculating the momentum thickness of the layer gave results in accord with the experimental determinations. Owing to practical difficulties in the exploration of the very thin boundary layers and in the determination of the velocity gradient around the surface, other comparisons with the theory (such as the progressive development of the boundary-layer velocity distribution and of the prediction of the separation point) were difficult. Nevertheless reasonable agreement between the theoretical and experimental velocity distributions was obtained particularly for the lower wind speed of the experiment, but no adequate test of the prediction of the separation point was found possible