16,422 research outputs found

    GAELS Project Final Report: Information environment for engineering

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    The GAELS project was a collaboration commenced in 1999 between Glasgow University Library and Strathclyde University Library with two main aims:· to develop collaborative information services in support of engineering research at the Universities of Glasgow and Strathclyde· to develop a CAL (computer-aided learning package) package in advanced information skills for engineering research students and staff The project was funded by the Scottish Higher Education Funding Council (SHEFC) from their Strategic Change Initiative funding stream, and funding was awarded initially for one year, with an extension of the grant for a further year. The project ended in June 2001.The funding from SHEFC paid for two research assistants, one based at Glasgow University Library working on collaborative information services and one based at Strathclyde University Library developing courseware. Latterly, after these two research assistants left to take up other posts, there has been a single researcher based at Glasgow University Library.The project was funded to investigate the feasibility of new services to the Engineering Faculties at both Universities, with a view to making recommendations for service provision that can be developed for other subject areas

    Large Pseudo-Counts and L2L_2-Norm Penalties Are Necessary for the Mean-Field Inference of Ising and Potts Models

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    Mean field (MF) approximation offers a simple, fast way to infer direct interactions between elements in a network of correlated variables, a common, computationally challenging problem with practical applications in fields ranging from physics and biology to the social sciences. However, MF methods achieve their best performance with strong regularization, well beyond Bayesian expectations, an empirical fact that is poorly understood. In this work, we study the influence of pseudo-count and L2L_2-norm regularization schemes on the quality of inferred Ising or Potts interaction networks from correlation data within the MF approximation. We argue, based on the analysis of small systems, that the optimal value of the regularization strength remains finite even if the sampling noise tends to zero, in order to correct for systematic biases introduced by the MF approximation. Our claim is corroborated by extensive numerical studies of diverse model systems and by the analytical study of the mm-component spin model, for large but finite mm. Additionally we find that pseudo-count regularization is robust against sampling noise, and often outperforms L2L_2-norm regularization, particularly when the underlying network of interactions is strongly heterogeneous. Much better performances are generally obtained for the Ising model than for the Potts model, for which only couplings incoming onto medium-frequency symbols are reliably inferred.Comment: 25 pages, 17 figure

    Single Maximal versus Combination Punch Kinematics

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    The aim of this study was to determine the influence of punch type (Jab, Cross, Lead Hook and Reverse Hook) and punch modality (Single maximal, ‘In-synch’ and ‘Out of synch’ combination) on punch speed and delivery time. Ten competition-standard volunteers performed punches with markers placed on their anatomical landmarks for 3D motion capture with an eight-camera optoelectronic system. Speed and duration between key moments were computed. There were significant differences in contact speed between punch types (F 2,18,84.87 = 105.76, p = 0.001) with Lead and Reverse Hooks developing greater speed than Jab and Cross. There were significant differences in contact speed between punch modalities (F 2,64,102.87 = 23.52, p = 0.001) with the Single maximal (M ± SD: 9.26 ± 2.09 m/s) higher than ‘Out of synch’ (7.49 ± 2.32 m/s), ‘In-synch’ left (8.01 ± 2.35 m/s) or right lead (7.97 ± 2.53 m/s). Delivery times were significantly lower for Jab and Cross than Hook. Times were significantly lower ‘In-synch’ than a Single maximal or ‘Out of synch’ combination mode. It is concluded that a defender may have more evasion-time than previously reported. This research could be of use to performers and coaches when considering training preparations

    Casimir-Polder forces, boundary conditions and fluctuations

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    We review different aspects of the atom-atom and atom-wall Casimir-Polder forces. We first discuss the role of a boundary condition on the interatomic Casimir-Polder potential between two ground-state atoms, and give a physically transparent interpretation of the results in terms of vacuum fluctuations and image atomic dipoles. We then discuss the known atom-wall Casimir-Polder force for ground- and excited-state atoms, using a different method which is also suited for extension to time-dependent situations. Finally, we consider the fluctuation of the Casimir-Polder force between a ground-state atom and a conducting wall, and discuss possible observation of this force fluctuation.Comment: 5 page

    Unitarity and the color confinement

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    We discuss how confinement property of QCD results in the rational unitarization scheme and how unitarity saturation leads to appearance of a hadron liquid phase at very high temperatures.Comment: 10 pages, no figire

    Structural disorder, magnetism, and electrical and thermoelectric properties of pyrochlore Nd2Ru2O7

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    Polycrystalline Nd2Ru2O7 samples have been prepared and examined using a combination of structural, magnetic, and electrical and thermal transport studies. Analysis of synchrotron X-ray and neutron diffraction patterns suggests some site disorder on the A-site in the pyrochlore sublattice: Ru substitutes on the Nd-site up to 7.0(3)%, regardless of the different preparative conditions explored. Intrinsic magnetic and electrical transport properties have been measured. Ru 4d spins order antiferromagnetically at 143 K as seen both in susceptibility and specific heat, and there is a corresponding change in the electrical resistivity behaviour. A second antiferromagnetic ordering transition seen below 10 K is attributed to ordering of Nd 4f spins. Nd2Ru2O7 is an electrical insulator, and this behaviour is believed to be independent of the Ru-antisite disorder on the Nd site. The electrical properties of Nd2Ru2O7 are presented in the light of data published on all A2Ru2O7 pyrochlores, and we emphasize the special structural role that Bi3+ ions on the A-site play in driving metallic behaviour. High-temperature thermoelectric properties have also been measured. When considered in the context of known thermoelectric materials with useful figures-of-merit, it is clear that Nd2Ru2O7 has excessively high electrical resistivity which prevents it from being an effective thermoelectric. A method for screening candidate thermoelectrics is suggested.Comment: 19 pages, 10 figure

    Quantitative proteomics in resected renal cancer tissue for biomarker discovery and profiling

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    <b>Background:</b>  Proteomics-based approaches for biomarker discovery are promising strategies used in cancer research. We present state-of-art label-free quantitative proteomics method to assess proteome of renal cell carcinoma (RCC) compared with noncancer renal tissues.<p></p> <b>Methods:</b>  Fresh frozen tissue samples from eight primary RCC lesions and autologous adjacent normal renal tissues were obtained from surgically resected tumour-bearing kidneys. Proteins were extracted by complete solubilisation of tissues using filter-aided sample preparation (FASP) method. Trypsin digested proteins were analysed using quantitative label-free proteomics approach followed by data interpretation and pathways analysis.<p></p> <b>Results:</b>  A total of 1761 proteins were identified and quantified with high confidence (MASCOT ion score threshold of 35 and P-value <0.05). Of these, 596 proteins were identified as differentially expressed between cancer and noncancer tissues. Two upregulated proteins in tumour samples (adipose differentiation-related protein and Coronin 1A) were further validated by immunohistochemistry. Pathway analysis using IPA, KOBAS 2.0, DAVID functional annotation and FLink tools showed enrichment of many cancer-related biological processes and pathways such as oxidative phosphorylation, glycolysis and amino acid synthetic pathways.<p></p> <b>Conclusions:<b>  Our study identified a number of differentially expressed proteins and pathways using label-free proteomics approach in RCC compared with normal tissue samples. Two proteins validated in this study are the focus of on-going research in a large cohort of patients.<p></p&gt

    Thermodynamic Scaling of the Viscosity of Van Der Waals, H-Bonded, and Ionic Liquids

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    Viscosities and their temperature, T, and volume, V, dependences are reported for 7 molecular liquids and polymers. In combination with literature viscosity data for 5 other liquids, we show that the superpositioning of relaxation times for various glass-forming materials when expressed as a function of TV^g, where the exponent g is a material constant, can be extended to the viscosity. The latter is usually measured to higher temperatures than the corresponding relaxation times, demonstrating the validity of the thermodynamic scaling throughout the supercooled and higher T regimes. The value of g for a given liquid principally reflects the magnitude of the intermolecular forces (e.g., steepness of the repulsive potential); thus, we find decreasing g in going from van der Waals fluids to ionic liquids. For strongly H-bonded materials, such as low molecular weight polypropylene glycol and water, the superpositioning fails, due to the non-trivial change of chemical structure (degree of H-bonding) with thermodynamic conditions.Comment: 16 pages 7 figure

    Phase diagram of a generalized ABC model on the interval

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    We study the equilibrium phase diagram of a generalized ABC model on an interval of the one-dimensional lattice: each site i=1,...,Ni=1,...,N is occupied by a particle of type \a=A,B,C, with the average density of each particle species N_\a/N=r_\a fixed. These particles interact via a mean field non-reflection-symmetric pair interaction. The interaction need not be invariant under cyclic permutation of the particle species as in the standard ABC model studied earlier. We prove in some cases and conjecture in others that the scaled infinite system N\rw\infty, i/N\rw x\in[0,1] has a unique density profile \p_\a(x) except for some special values of the r_\a for which the system undergoes a second order phase transition from a uniform to a nonuniform periodic profile at a critical temperature Tc=3rArBrC/2Ï€T_c=3\sqrt{r_A r_B r_C}/2\pi.Comment: 25 pages, 6 figure
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