249 research outputs found

    MD simulations of 1,4 - polybutadiene at graphite surfaces

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    The English cotton spinning industry, 1780–1840, as revealed in the columns of the London Gazette

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    We investigate the early development of English cotton spinning by analyzing about 700 bankruptcies and 1300 dissolutions of partnership reported in the London Gazette, 1770–1840. The data show two temporal cycles, peaking in the early to mid-1800s and in the later 1820s, near the ends of investment booms. Both earlier peaks were absolutely higher than the later, despite industry growth. Over time both bankruptcies and dissolutions show the concentration of spinning in greater Lancashire, and within greater Lancashire in the surrounding towns rather than in Manchester. The industry was dominated by single proprietors or firms with only two partners and integration with weaving was steadily increasing. The paper demonstrates the potential of the Gazette, now searchable online, as a source for business and industrial history

    The English cotton spinning industry, 1780–1840, as revealed in the columns of the London Gazette

    Get PDF
    We investigate the early development of English cotton spinning by analyzing about 700 bankruptcies and 1300 dissolutions of partnership reported in the London Gazette, 1770–1840. The data show two temporal cycles, peaking in the early to mid-1800s and in the later 1820s, near the ends of investment booms. Both earlier peaks were absolutely higher than the later, despite industry growth. Over time both bankruptcies and dissolutions show the concentration of spinning in greater Lancashire, and within greater Lancashire in the surrounding towns rather than in Manchester. The industry was dominated by single proprietors or firms with only two partners and integration with weaving was steadily increasing. The paper demonstrates the potential of the Gazette, now searchable online, as a source for business and industrial history

    Development and implementation of rapid metabolic engineering tools for chemical and fuel production in Geobacillus thermoglucosidasius NCIMB 11955

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    Background The thermophile Geobacillus thermoglucosidasius has considerable attraction as a chassis for the production of chemicals and fuels. It utilises a wide range of sugars and oligosaccharides typical of those derived from lignocellulose and grows at elevated temperatures. The latter improves the rate of feed conversion, reduces fermentation cooling costs and minimises the risks of contamination. Full exploitation of its potential has been hindered by a dearth of effective gene tools. Results Here we designed and tested a collection of vectors (pMTL60000 series) in G. thermoglucosidasius NCIMB 11955 equivalent to the widely used clostridial pMTL80000 modular plasmid series. By combining a temperature-sensitive replicon and a heterologous pyrE gene from Geobacillus kaustophilus as a counter-selection marker, a highly effective and rapid gene knock-out/knock-in system was established. Its use required the initial creation of uracil auxotroph through deletion of pyrE using allele-coupled exchange (ACE) and selection for resistance to 5-fluoroorotic acid. The turnaround time for the construction of further mutants in this pyrE minus strain was typically 5 days. Following the creation of the desired mutant, the pyrE allele was restored to wild type, within 3 days, using ACE and selection for uracil prototrophy. Concomitant with this process, cargo DNA (pheB) could be readily integrated at the pyrE locus. The system’s utility was demonstrated through the generation in just 30 days of three independently engineered strains equivalent to a previously constructed ethanol production strain, TM242. This involved the creation of two in-frame deletions (ldh and pfl) and the replacement of a promoter region of a third gene (pdh) with an up-regulated variant. In no case did the production of ethanol match that of TM242. Genome sequencing of the parental strain, TM242, and constructed mutant derivatives suggested that NCIMB 11955 is prone to the emergence of random mutations which can dramatically affect phenotype. Conclusions The procedures and principles developed for clostridia, based on the use of pyrE alleles and ACE, may be readily deployed in G. thermoglucosidasius. Marker-less, in-frame deletion mutants can be rapidly generated in 5 days. However, ancillary mutations frequently arise, which can influence phenotype. This observation emphasises the need for improved screening and selection procedures at each step of the engineering processes, based on the generation of multiple, independent strains and whole-genome sequencing

    Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton–proton collisions at the LHC

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    This paper presents the method and performance of primary vertex reconstruction in proton–proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of √s=8 TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about 30μm is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than 20μm and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing
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