Improved Landau Gauge Fixing and Discretisation Errors

Lattice discretisation errors in the Landau gauge condition are examined. An improved gauge fixing algorithm in which order a^2 errors are removed is presented. Order a^2 improvement of the gauge fixing condition displays the secondary benefit of reducing the size of higher-order errors. These results emphasise the importance of implementing an improved gauge fixing condition.Comment: LATTICE99 (Improvement and Renormalization), 3 pages, 1 figur

The internationalisation of the Jamaican manufacturing micro small and medium enterprise: The impact of standards as a potential firm resource

This thesis addressed the critical issue of the paucity in exporting by Jamaican manufacturing Micro Small and Medium Enterprises (MSMEs) even though these MSMEs are the key pillars of Jamaica’s economy. The purpose of this thesis was to address the gap in literature with respect to Jamaican MSMEs as well as to investigate the use of standards as an additional firm resource for increasing competitiveness and internationalising on a global scale. To gather data, the listings of registered manufacturers and exporters were obtained from the Jamaica Manufacturers and Exporters Association (JMEA) and the Jamaica Promotions Corporation (JAMPRO). Both databases were merged, and all redundancies were removed. Analysis of the population database revealed that these MSMEs were operating within seven industrial sectors, namely agro-processing/food & juices, chemicals, cosmetics and pharmaceuticals, electrical, furniture, minerals, metal products, doors and glass, printing & packaging and textiles & sewn products. A survey instrument was then issued to 387 MSMEs of which only 89 responded. Additionally, 3 case studies were developed from in-depth interviews with 3 of these MSMEs who responded to the survey; one was an established exporter while the other two did not export consistently. The themes which arose from the research included manufacturing, entrepreneurship, export stimuli and internationalisation; these themes were all addressed from a strategic management perspective. Variables such as investment in standards (IS), manufacturing strategy (MS), entrepreneurial orientation (EO), competitive strategy (CS), number of employees (NEM), entrepreneur foreign language (EFL), entrepreneur foreign work experience (EFWE), entrepreneur foreign study and living (EFSL), entrepreneur education (EDU), age of firm (AF), family owned or not (FON) and the environment (EnF) were all analysed to determine their impact on internationalisation. The data was analysed by using correlation analysis, logit regression and analysis of variance (ANOVA). Principal Component Analysis, a factor analysis technique was used to determine the amount of variance in the data. A single factor MS was retained after extraction (using the default cut off criterion for extraction: eigenvalues over 1), and this factor or variable explained approximately 23% of the total variance in the 12 observed variables. Five models were developed to provide answers to MSMEs internationalisation in Jamaica. Model 1 investigated the impact the control variables AF and family owned or not (FON) had on internationalisation and the result demonstrated that there was not any significance. Model 2 considered all 12 variables, and this too was insignificant. However, Model 3 demonstrated that MS was the only variable that had any significance with respect to the internationalisation process despite its negative correlation; the F test had a p value of .027 where p < .05, therefore, the overall model was statistically significant. Interestingly, Model 4 demonstrated significance between manufacturing strategy and internationalisation in the non-agroprocessing industry; the F test had a p value of .028 where p < .05. Model 5 investigated the moderating effect that the EnF had on IS as a firm resource but despite the fact that the environment and investment in standards were negatively correlated, there was not enough evidence from logistic regression to conclude that the environment had a moderating effect on investment in standards.The practical implications for this study are that the export model developed will assist government and private sector policymakers to assist in providing a more enabling business environment for Jamaican MSMEs to operate. It should make them take practical steps to eliminate the several bureaucratic processes which stifle and strangle doing business in Jamaica. Entrepreneurs who manage small firms should be better able to strategise the configuration of available resources to compete efficiently and boost their enterprises chances of internationalising. These strategies and policies developed will improve the stimulus for nonexporters to become exporters and current exporters to increase the yield of their exports. The export model will also be useful for Jamaica’s CARICOM neighbours to emulate

A Pinhole Camera for Radiation Research in Dentistry

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68035/2/10.1177_00220345620410013201.pd

Excited Baryons from the FLIC Fermion Action

Masses of positive and negative parity excited nucleons and hyperons are calculated in quenched lattice QCD using an O(a^2) improved gluon action and a fat-link clover fermion action in which only the irrelevant operators are constructed with fat links. The results are in agreement with earlier N* simulations with improved actions, and exhibit a clear mass splitting between the nucleon and its parity partner, as well as a small mass splitting between the two low-lying J^P={1/2}^- N* states. Study of different Lambda interpolating fields suggests a similar splitting between the lowest two {1/2}^- Lambda* states, although the empirical mass suppression of the Lambda*(1405) is not seen.Comment: 3 pages, 3 figures, Lattice2002(QCD Spectrum and Quark Masses

Baryon resonances from a novel fat-link fermion action

We present first results for masses of positive and negative parity excited baryons in lattice QCD using an O(a^2) improved gluon action and a Fat Link Irrelevant Clover (FLIC) fermion action in which only the irrelevant operators are constructed with fat links. The results are in agreement with earlier calculations of N^* resonances using improved actions and exhibit a clear mass splitting between the nucleon and its chiral partner, even for the Wilson fermion action. The results also indicate a splitting between the lowest J^P = 1/2^- states for the two standard nucleon interpolating fields.Comment: 5 pages, 3 figures, talk given by W.Melnitchouk at LHP 2001 workshop, Cairns, Australi

Model predictive control application to spacecraft rendezvous in mars sample return scenario

Model Predictive Control (MPC) is an optimization-based control strategy that is considered extremely attractive in the autonomous space rendezvous scenarios. The Online Recon¦guration Control System and Avionics Architecture (ORCSAT) study addresses its applicability in Mars Sample Return (MSR) mission, including the implementation of the developed solution in a space representative avionic architecture system. With respect to a classical control solution High-integrity Autonomous RendezVous and Docking control system (HARVD), MPC allows a signi¦cant performance improvement both in trajectory and in propellant save. Furthermore, thanks to the online optimization, it allows to identify improvements in other areas (i. e., at mission de¦nition level) that could not be known a priori

A Bayesian Approach to Calibrating Period-Luminosity Relations of RR Lyrae Stars in the Mid-Infrared

A Bayesian approach to calibrating period-luminosity (PL) relations has substantial benefits over generic least-squares fits. In particular, the Bayesian approach takes into account the full prior distribution of the model parameters, such as the a priori distances, and refits these parameters as part of the process of settling on the most highly-constrained final fit. Additionally, the Bayesian approach can naturally ingest data from multiple wavebands and simultaneously fit the parameters of PL relations for each waveband in a procedure that constrains the parameter posterior distributions so as to minimize the scatter of the final fits appropriately in all wavebands. Here we describe the generalized approach to Bayesian model fitting and then specialize to a detailed description of applying Bayesian linear model fitting to the mid-infrared PL relations of RR Lyrae variable stars. For this example application we quantify the improvement afforded by using a Bayesian model fit. We also compare distances previously predicted in our example application to recently published parallax distances measured with the Hubble Space Telescope and find their agreement to be a vindication of our methodology. Our intent with this article is to spread awareness of the benefits and applicability of this Bayesian approach and encourage future PL relation investigations to consider employing this powerful analysis method.Comment: 6 pages, 1 figure. Accepted for publication in Astrophysics & Space Science. Following a presentation at the conference The Fundamental Cosmic Distance Scale: State of the Art and the Gaia Perspective, Naples, May 201

Genetic partitioning of interleukin-6 signalling in mice dissociates Stat3 from Smad3-mediated lung fibrosis

Idiopathic pulmonary fibrosis (IPF) is a fatal disease that is unresponsive to current therapies and characterized by excessive collagen deposition and subsequent fibrosis. While inflammatory cytokines, including interleukin (IL)-6, are elevated in IPF, the molecular mechanisms that underlie this disease are incompletely understood, although the development of fibrosis is believed to depend on canonical transforming growth factor (TGF)-β signalling. We examined bleomycin-induced inflammation and fibrosis in mice carrying a mutation in the shared IL-6 family receptor gp130. Using genetic complementation, we directly correlate the extent of IL-6-mediated, excessive Stat3 activity with inflammatory infiltrates in the lung and the severity of fibrosis in corresponding gp130757F mice. The extent of fibrosis was attenuated in B lymphocyte-deficient gp130757F;µMT−/− compound mutant mice, but fibrosis still occurred in their Smad3−/− counterparts consistent with the capacity of excessive Stat3 activity to induce collagen 1α1 gene transcription independently of canonical TGF-β/Smad3 signalling. These findings are of therapeutic relevance, since we confirmed abundant STAT3 activation in fibrotic lungs from IPF patients and showed that genetic reduction of Stat3 protected mice from bleomycin-induced lung fibrosis

Spin-3/2 baryons in lattice QCD

Copyright © 2003. Elsevier. Printed in U.S.A. Submitted to Cornell University’s online archive www.arXiv.org in 2003 by James Zanotti. Post-print sourced from www.arxiv.org.We present first results for masses of spin-3/2 baryons in lattice QCD, using a novel fat-link clover fermion action in which only the irrelevant operators are constructed using fat links. In the isospin-1/2 sector, we observe, after appropriate spin and parity projection, a strong signal for the J^P=3/2^- state, and find good agreement between the 1/2^+ mass and earlier nucleon mass simulations with a spin-1/2 interpolating field. For the isospin-3/2 Delta states, clear mass splittings are observed between the various 1/2^+/- and 3/2^+/- channels, with the calculated level orderings in good agreement with those observed empirically.J.M. Zanotti, S. Choe, D.B. Leinweber, W. Melnitchouk, A.G. Williams, and J.B. Zhanghttp://www.elsevier.com/wps/find/journaldescription.cws_home/505717/description#descriptio