62,371 research outputs found
Vanishing viscosity limits of mixed hyperbolic–elliptic systems arising in multilayer channel flows
Tempo and intensity of pre-task music modulate neural activity during reactive task performance
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2013 The Authors.Research has shown that not only do young athletes purposively use music to manage their emotional state (Bishop, Karageorghis, & Loizou, 2007), but also that brief periods of music listening may facilitate their subsequent reactive performance (Bishop, Karageorghis, & Kinrade, 2009). We report an fMRI study in which young athletes lay in an MRI scanner and listened to a popular music track immediately prior to performance of a three-choice reaction time task; intensity and tempo were modified such that six excerpts (2 intensities × 3 tempi) were created. Neural activity was measured throughout. Faster tempi and higher intensity collectively yielded activation in structures integral to visual perception (inferior temporal gyrus), allocation of attention (cuneus, inferior parietal lobule, supramarginal gyrus), and motor control (putamen), during reactive performance. The implications for music listening as a pre-competition strategy in sport are discussed
The Rhesus Factor and Disease Prevention
First published by the Wellcome Trust Centre
for the History of Medicine at UCL, 2004. ©The Trustee of the Wellcome Trust, London, 2004. All volumes are freely available online at: www.history.qmul.ac.uk/research/modbiomed/wellcome_witnesses/Annotated and edited transcript of a Witness Seminar held on 3 June 2003. Introduction by Professor Doris T Zallen.Annotated and edited transcript of a Witness Seminar held on 3 June 2003. Introduction by Professor Doris T Zallen.Annotated and edited transcript of a Witness Seminar held on 3 June 2003. Introduction by Professor Doris T Zallen.Annotated and edited transcript of a Witness Seminar held on 3 June 2003. Introduction by Professor Doris T Zallen.Annotated and edited transcript of a Witness Seminar held on 3 June 2003. Introduction by Professor Doris T Zallen.Annotated and edited transcript of a Witness Seminar held on 3 June 2003. Introduction by Professor Doris T Zallen.Consists of the edited transcripts of Witness SeThe prevention of rhesus disease of the newborn is a stunning medical success story. This disease afflicted thousands of newborns each year, causing serious health problems, even death. Yet from the early 1940s to the 1970s – British and American researchers uncovered the basis of the disease and developed the medical intervention that could prevent its occurrence. Many of the key steps leading to this remarkable achievement took place at the University of Liverpool School of Medicine. Chaired by Professor Sir David Weatherall, this Witness Seminar examines the factors that triggered these studies and the challenges that confronted scientists and clinicians; the intellectual, institutional, and social factors that guided the work; the crucial insights; and the vistas that the prevention of rhesus disease has opened in fetal medicine. Participants include Professor Robin Coombs, the late Professor Ronald Finn, Dr Nevin Hughes-Jones, Professor Patrick Mollison, Dr Archie Norman, Dr Derrick Tovey, Professor Charles Whitfield, Professor John Woodrow and Professor Doris Zallen. Zallen, D T, Christie D A, Tansey E M. (eds) (2004) The Rhesus factor and disease prevention, Wellcome Witnesses to Twentieth Century Medicine, vol. 22. London: The Wellcome Trust Centre for the History of Medicine at UCL. ISBN 978 0 85484 099 1minars organized by the History of Twentieth Century Medicine Group and held at the Wellcome Institute for the History of Medicine.The Wellcome Trust Centre for the History of Medicine at University College London is funded by the Wellcome Trust,which is a registered charity, no. 210183
Faster K-Means Cluster Estimation
There has been considerable work on improving popular clustering algorithm
`K-means' in terms of mean squared error (MSE) and speed, both. However, most
of the k-means variants tend to compute distance of each data point to each
cluster centroid for every iteration. We propose a fast heuristic to overcome
this bottleneck with only marginal increase in MSE. We observe that across all
iterations of K-means, a data point changes its membership only among a small
subset of clusters. Our heuristic predicts such clusters for each data point by
looking at nearby clusters after the first iteration of k-means. We augment
well known variants of k-means with our heuristic to demonstrate effectiveness
of our heuristic. For various synthetic and real-world datasets, our heuristic
achieves speed-up of up-to 3 times when compared to efficient variants of
k-means.Comment: 6 pages, Accepted at ECIR 201
A High-Throughput Solver for Marginalized Graph Kernels on GPU
We present the design and optimization of a linear solver on General Purpose GPUs for the efficient and high-throughput evaluation of the marginalized graph kernel between pairs of labeled graphs. The solver implements a preconditioned conjugate gradient (PCG) method to compute the solution to a generalized Laplacian equation associated with the tensor product of two graphs. To cope with the gap between the instruction throughput and the memory bandwidth of current generation GPUs, our solver forms the tensor product linear system on-the-fly without storing it in memory when performing matrix-vector dot product operations in PCG. Such on-the-fly computation is accomplished by using threads in a warp to cooperatively stream the adjacency and edge label matrices of individual graphs by small square matrix blocks called tiles, which are then staged in registers and the shared memory for later reuse. Warps across a thread block can further share tiles via the shared memory to increase data reuse. We exploit the sparsity of the graphs hierarchically by storing only non-empty tiles using a coordinate format and nonzero elements within each tile using bitmaps. Besides, we propose a new partition-based reordering algorithm for aggregating nonzero elements of the graphs into fewer but denser tiles to improve the efficiency of the sparse format.We carry out extensive theoretical analyses on the graph tensor product primitives for tiles of various density and evaluate their performance on synthetic and real-world datasets. Our solver delivers three to four orders of magnitude speedup over existing CPU-based solvers such as GraKeL and GraphKernels. The capability of the solver enables kernel-based learning tasks at unprecedented scales
Characterization of the definitive classical calpain family of vertebrates using phylogenetic, evolutionary and expression analyses
Peer reviewedPublisher PD
Protein-RNA interactions: a structural analysis
A detailed computational analysis of 32 protein-RNA complexes is presented. A number of physical and chemical properties of the intermolecular interfaces are calculated and compared with those observed in protein-double-stranded DNA and protein-single-stranded DNA complexes. The interface properties of the protein-RNA complexes reveal the diverse nature of the binding sites. van der Waals contacts played a more prevalent role than hydrogen bond contacts, and preferential binding to guanine and uracil was observed. The positively charged residue, arginine, and the single aromatic residues, phenylalanine and tyrosine, all played key roles in the RNA binding sites. A comparison between protein-RNA and protein-DNA complexes showed that whilst base and backbone contacts (both hydrogen bonding and van der Waals) were observed with equal frequency in the protein-RNA complexes, backbone contacts were more dominant in the protein-DNA complexes. Although similar modes of secondary structure interactions have been observed in RNA and DNA binding proteins, the current analysis emphasises the differences that exist between the two types of nucleic acid binding protein at the atomic contact level
Self-Employment and Risk Preference
We explore the relationship between self-employment and attitudes towards financial risk using individual level data drawn from the U.S. Survey of Consumer Finances (SCF) and the U.S. Panel Study of Income Dynamics (PSID). Both surveys include questions, which enable us to construct measures of an individual´s willingness to take risk allowing us to explore the implications of interpersonal differences in risk preference for the probability and success of self-employment. Our empirical findings suggest that willingness to take financial risk is positively associated with both the incidence and success of self-employment. We find that this relationship is particularly pronounced in cases where the individual actually started the business. Finally, we exploit the panel aspect of the PSID and find evidence consistent with a causal relationship between attitudes towards risk and self-employment with attitudes towards risk measured over 1969-1972 (i.e. prior to becoming self-employed) having a statistically significant positive influence on the probability of self-employment in 1996
SPLENIC HOMOTRANSPLANTATION.
During the past 12 months, five clinical whole-organ splenic homotransplantations have been carried out with the objective of providing active immunologic tissue for the recipient patients. In one case with hypogammaglobulinemia, it was hoped that the transplanted tissue would alleviate a state of immunologic deficiency. In the other four, all of whom had terminal malignancies, the purpose was to superimpose a state of altered immunologic reactivity upon the host in the hope of thereby suppressing the inexorable growth of the neoplasms. As will be described, these procedures can now be judged in each instance to have been without benefit. Nevertheless, full documentation of the cases seems justified not only because of the many implications of transplantation of immunologically competent tissue, but also because of the potentially important observations made during the care of these patients. In addition, a full account will be presented of the supporting canine studies of splenic homotransplantation, inasmuch as many of the principles of clinical therapy and investigation derived from prior observations in the dog. The fact that it is possible to obtain viable splenic homografts in the dog for as long as two-thirds of a year without the production of runt disease or other harmful effects may have application in future research on bone marrow, other lymphoid, or hepatic homografts
- …
