1,811 research outputs found

    Law, politics and the governance of English and Scottish joint-stock companies 1600-1850

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    This article examines the impact of law on corporate governance by means of a case study of joint-stock enterprise in England and Scotland before 1850. Based on a dataset of over 450 company constitutions together with qualitative information on governance practice, it finds little evidence to support the hypothesis that common-law regimes such as England were more supportive of economic growth than civil-law jurisdictions such as Scotland: indeed, levels of shareholder protection were slightly stronger in the civil-law zone. Other factors, such as local political institutions, played a bigger role in shaping organisational forms and business practice

    Measuring Global Credibility with Application to Local Sequence Alignment

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    Computational biology is replete with high-dimensional (high-D) discrete prediction and inference problems, including sequence alignment, RNA structure prediction, phylogenetic inference, motif finding, prediction of pathways, and model selection problems in statistical genetics. Even though prediction and inference in these settings are uncertain, little attention has been focused on the development of global measures of uncertainty. Regardless of the procedure employed to produce a prediction, when a procedure delivers a single answer, that answer is a point estimate selected from the solution ensemble, the set of all possible solutions. For high-D discrete space, these ensembles are immense, and thus there is considerable uncertainty. We recommend the use of Bayesian credibility limits to describe this uncertainty, where a (1−α)%, 0≤α≤1, credibility limit is the minimum Hamming distance radius of a hyper-sphere containing (1−α)% of the posterior distribution. Because sequence alignment is arguably the most extensively used procedure in computational biology, we employ it here to make these general concepts more concrete. The maximum similarity estimator (i.e., the alignment that maximizes the likelihood) and the centroid estimator (i.e., the alignment that minimizes the mean Hamming distance from the posterior weighted ensemble of alignments) are used to demonstrate the application of Bayesian credibility limits to alignment estimators. Application of Bayesian credibility limits to the alignment of 20 human/rodent orthologous sequence pairs and 125 orthologous sequence pairs from six Shewanella species shows that credibility limits of the alignments of promoter sequences of these species vary widely, and that centroid alignments dependably have tighter credibility limits than traditional maximum similarity alignments

    Antenatal preventative pelvic floor muscle exercise intervention led by midwives to reduce postnatal urinary incontinence (APPEAL): protocol for a feasibility and pilot cluster randomised controlled trial

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    Background: Antenatal pelvic floor muscle exercises (PFME) in women without prior urinary incontinence (UI) are effective in reducing postnatal UI; however, UK midwives often do not provide advice and information to women on undertaking PFME, with evidence that among women who do receive advice, many do not perform PFME. Methods: The primary aim of this feasibility and pilot cluster randomised controlled trial is to provide a potential assessment of the feasibility of undertaking a future definitive trial of a midwifery-led antenatal intervention to support women to perform PFME in pregnancy and reduce UI postnatally. Community midwifery teams in participating NHS sites comprise trial clusters (n = 17). Midwives in teams randomised to the intervention will be trained on how to teach PFME to women and how to support them in undertaking PFME in pregnancy. Women whose community midwifery teams are allocated to control will receive standard antenatal care only. All pregnant women who give birth over a pre-selected sample month who receive antenatal care from participating community midwifery teams (clusters) will be sent a questionnaire at 10–12 weeks postpartum (around 1400–1500 women). Process evaluation data will include interviews with midwives to assess if the intervention could be implemented as planned. Interviews with women in both trial arms will explore their experiences of support from midwives to perform PFME during pregnancy. Data will be stored securely at the Universities of Birmingham and Exeter. Results will be disseminated through publications aimed at maternity service users, clinicians, and academics and inform a potential definitive trial of effectiveness. The West Midlands–Edgbaston Research Ethics Committee approved the study protocol. Discussion: Trial outcomes will determine if criteria to progress to a definitive cluster trial are met. These include women’s questionnaire return rates, prevalence of UI, and other health outcomes as reported by women at 10–12 weeks postpartum. Progress to a definitive trial however is likely to be prevented in the UK context by new perinatal pelvic health service, although this may be possible elsewhere. Trial registration: https://doi.org/10.1186/ISRCTN10833250. Registered 09/03/202

    A 31 GHz Survey of Low-Frequency Selected Radio Sources

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    The 100-m Robert C. Byrd Green Bank Telescope (GBT) and the Owens Valley Radio Observatory (OVRO) 40-m radio telescope have been used to conduct a survey of 3165 known extragalactic radio sources over 143 square degrees of the sky. Target sources were selected from the NRAO VLA Sky Survey in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGN) with 1.4 GHz flux densities of 3 to 10 mJy. The resulting 31 GHz catalogs are presented in full online. Using a Maximum-Likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4 to 31 GHz spectral indices of these sources, we find a mean 31 to 1.4 GHz flux ratio of 0.110 +/- 0.003 corresponding to a spectral index of alpha=-0.71 +/- 0.01 (S ~ nu^alpha); 9.0 +/- 0.8 % of sources have alpha > -0.5 and 1.2 +/- 0.2 % have alpha > 0. By combining this spectral index distribution with 1.4 GHz source counts we predict 31 GHz source counts in the range 1 mJy < S_31 < 4 mJy, N(>S_31) = (16.7 +/- 1.7) deg^2 (S_31/1 mJy)^(-0.80 +/- 0.07). We also assess the contribution of mJy-level (S_1.4 < 3.4 mJy) radio sources to the 31 GHz CMB power spectrum, finding a mean power of ell (ell+1) C^src_ell/(2 pi) = 44 +/- 14 micro-Kelvin^2 and a 95% upper limit of 80 micro-Kelvin^2 at ell = 2500. Including an estimated contribution of 12 micro-Kelvin^2 from the population of sources responsible for the turn-up in counts below S_1.4 = 1 mJy this amounts to 21 +/- 7 % of what is needed to explain the CBI high-ell excess signal, 275 +/- 63 micro-Kelvin^2. These results are consistent with other measurements of the 31 GHz point source foreground.Comment: Replace with accepted version, incorporating referee comments. Significant revisions for clarity, added comparison to recent results. Quoted error bars on source counts are larger and the range of validity more limited; results on CBI excess unchange

    Accurate and Rapid Identification of the Burkholderia pseudomallei Near-Neighbour, Burkholderia ubonensis, Using Real-Time PCR

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    Burkholderia ubonensis is an environmental bacterium belonging to the Burkholderia cepacia complex (Bcc), a group of genetically related organisms that are associated with opportunistic but generally nonfatal infections in healthy individuals. In contrast, the near-neighbour species Burkholderia pseudomallei causes melioidosis, a disease that can be fatal in up to 95% of cases if left untreated. B. ubonensis is frequently misidentified as B. pseudomallei from soil samples using selective culturing on Ashdown&rsquo;s medium, reflecting both the shared environmental niche and morphological similarities of these species. Additionally, B. ubonensis shows potential as an important biocontrol agent in B. pseudomallei-endemic regions as certain strains possess antagonistic properties towards B. pseudomallei. Current methods for characterising B. ubonensis are laborious, time-consuming and costly, and as such this bacterium remains poorly studied. The aim of our study was to develop a rapid and inexpensive real-time PCR-based assay specific for B. ubonensis. We demonstrate that a novel B. ubonensis-specific assay, Bu550, accurately differentiates B. ubonensis from B. pseudomallei and other species that grow on selective Ashdown&rsquo;s agar. We anticipate that Bu550 will catalyse research on B. ubonensis by enabling rapid identification of this organism from Ashdown&rsquo;s-positive colonies that are not B. pseudomallei

    Directed Assembly of Homopentameric Cholera Toxin B‑Subunit Proteins into Higher-Order Structures Using Coiled-Coil Appendages

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    The self-assembly of proteins into higher order structures is ubiquitous in living systems. It is also an essential process for the bottom-up creation of novel molecular architectures and devices for synthetic biology. However, the complexity of protein-protein interaction surfaces makes it challenging to mimic natural assembly processes in artificial systems. Indeed, many successful computationally designed protein assemblies are pre-screened for ‘designability’, limiting the choice of components. Here, we report a simple and pragmatic strategy to assemble chosen multi-subunit proteins into more complex structures. A coiled-coil domain appended to one face of the pentameric cholera toxin B-subunit (CTB) enabled the ordered assembly of tubular supra-molecular complexes. X-ray crystallography and analysis of a tubular structure has revealed a hierarchical assembly process that displays features reminiscent of the polymorphic assembly of polyomavirus proteins. The approach provides a simple and straightforward method to direct the assembly of protein building blocks which present either termini on a single face of an oligomer. This scaffolding approach can be used to generate bespoke supramolecular assemblies of functional proteins. Additionally, structural resolution of the scaffolded assemblies highlight ‘native-state’ forced protein-protein interfaces, which may prove useful as starting conformations for future computational design

    PKS 1502+106: a new and distant gamma-ray blazar in outburst discovered by the Fermi Large Area Telescope

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    The Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope discovered a rapid (about 5 days duration), high-energy (E >100 MeV) gamma-ray outburst from a source identified with the blazar PKS 1502+106 (OR 103, S3 1502+10, z=1.839) starting on August 05, 2008 and followed by bright and variable flux over the next few months. Results on the gamma-ray localization and identification, as well as spectral and temporal behavior during the first months of the Fermi all-sky survey are reported here in conjunction with a multi-waveband characterization as a result of one of the first Fermi multi-frequency campaigns. The campaign included a Swift ToO (followed up by 16-day observations on August 07-22, MJD 54685-54700), VLBA (within the MOJAVE program), Owens Valley (OVRO) 40m, Effelsberg-100m, Metsahovi-14m, RATAN-600 and Kanata-Hiroshima radio/optical observations. Results from the analysis of archival observations by INTEGRAL, XMM-Newton and Spitzer space telescopes are reported for a more complete picture of this new gamma-ray blazar.Comment: 17 pages, 11 figures, accepted for The Astrophysical Journa

    Organism-sediment interactions govern post-hypoxia recovery of ecosystem functioning

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    Hypoxia represents one of the major causes of biodiversity and ecosystem functioning loss for coastal waters. Since eutrophication-induced hypoxic events are becoming increasingly frequent and intense, understanding the response of ecosystems to hypoxia is of primary importance to understand and predict the stability of ecosystem functioning. Such ecological stability may greatly depend on the recovery patterns of communities and the return time of the system properties associated to these patterns. Here, we have examined how the reassembly of a benthic community contributed to the recovery of ecosystem functioning following experimentally-induced hypoxia in a tidal flat. We demonstrate that organism-sediment interactions that depend on organism size and relate to mobility traits and sediment reworking capacities are generally more important than recovering species richness to set the return time of the measured sediment processes and properties. Specifically, increasing macrofauna bioturbation potential during community reassembly significantly contributed to the recovery of sediment processes and properties such as denitrification, bedload sediment transport, primary production and deep pore water ammonium concentration. Such bioturbation potential was due to the replacement of the small-sized organisms that recolonised at early stages by large-sized bioturbating organisms, which had a disproportionately stronger influence on sediment. This study suggests that the complete recovery of organism-sediment interactions is a necessary condition for ecosystem functioning recovery, and that such process requires long periods after disturbance due to the slow growth of juveniles into adult stages involved in these interactions. Consequently, repeated episodes of disturbance at intervals smaller than the time needed for the system to fully recover organism-sediment interactions may greatly impair the resilience of ecosystem functioning.

    A plan for play - An Eye View Series report

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    There is a simple, inexpensive and joyful way to address many of the major challenges facing society and its children; addressing the alarming mental health crisis and obesity epidemic and helping to prepare children for an ever-changing work force. The solution that is all too often overlooked and neglected is - play. The right to play is so important that it is enshrined in the UN Convention on the Rights of the Child. Research documents its importance to every aspect of child health, development and wellbeing. Yet many children have little or no access to high quality play opportunities. Play provision should be considered in relation to every aspect of children’s lives – the design of their neighbourhoods, as well as within the services they access, such as child care centres, schools, hospitals, recreation facilities, parks and adventure playgrounds. Play cannot be relegated to the places and context that adults decide are appropriate It should be woven into the fabric of every aspect of children’s lives and the communities they are part of. Equitable access to play means reducing the insidious gradient of inequity that impacts children’s lives even before they are born and continues across their lifespan. Schools are one important venue to ensure equitable access to play. For some children, it will be the only opportunity they have for this nourishing and necessary activity. Play comprises a quarter of the school year, yet teachers and support staff receive no proper training or support to ensure that children in their care – our society’s future – have fulfilling play time. We know that early life experiences set the stage for the future, and that early intervention saves unquantifiable and unnecessary suffering and costs later on – for children, families and society as a whole. We owe it to children and ourselves both now and tomorrow, to make a plan for play that sees every child in every place playing every day. This report makes that case

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
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