827 research outputs found

    On the Complexity of Temporal-Logic Path Checking

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    Given a formula in a temporal logic such as LTL or MTL, a fundamental problem is the complexity of evaluating the formula on a given finite word. For LTL, the complexity of this task was recently shown to be in NC. In this paper, we present an NC algorithm for MTL, a quantitative (or metric) extension of LTL, and give an NCC algorithm for UTL, the unary fragment of LTL. At the time of writing, MTL is the most expressive logic with an NC path-checking algorithm, and UTL is the most expressive fragment of LTL with a more efficient path-checking algorithm than for full LTL (subject to standard complexity-theoretic assumptions). We then establish a connection between LTL path checking and planar circuits, which we exploit to show that any further progress in determining the precise complexity of LTL path checking would immediately entail more efficient evaluation algorithms than are known for a certain class of planar circuits. The connection further implies that the complexity of LTL path checking depends on the Boolean connectives allowed: adding Boolean exclusive or yields a temporal logic with P-complete path-checking problem

    Prevalence and number of Salmonella in retail pork sausages

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    The aim of this study was to assess the prevalence of Salmonella in Irish pork sausage at retail level. Samples, comprising branded prepacked sausages, loose sausages from supermarket meat counters and butcher shops, were collected from selected retail sites in four cities from October to December 2001 and from June to August 2002. A 3-tube Most Probable Number (MPN) method was used to enumerate Salmonella in a selected number of samples, which were positive by enrichment. Salmonella serotypes were detected in 4.4% and 1.7% of samples at each of the respective sampling periods; a level similar to those reported in other U.S. and U.K. studies. Limited results available on enumeration suggest that contamination rates were low. This study revealed that Salmonella are present in a proportion of Irish sausages and further risk analysis work is necessary in order to quantify the risk posed to public health. Keywords: control programme, enumeration, serology, bacteriology, food safety

    Structure, Deformations and Gravitational Wave Emission of Magnetars

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    Neutron stars can have, in some phases of their life, extremely strong magnetic fields, up to 10^15-10^16 G. These objects, named magnetars, could be powerful sources of gravitational waves, since their magnetic field could determine large deformations. We discuss the structure of the magnetic field of magnetars, and the deformation induced by this field. Finally, we discuss the perspective of detection of the gravitational waves emitted by these stars.Comment: 11 pages, 2 figures, prepared for 19th International Conference on General Relativity and Gravitation (GR19), Mexico City, Mexico, July 5-9, 201

    Investigation of MRSA transmission between pigs and the environment following intra-nasal inoculation

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    Meticillin-resistant Staphylococcus aureus (MRSA) ST398 has not been detected in pigs in Ireland. However, other strains of MRSA, including MRSA t002, have been isolated from animals and humans in Ireland. The aim of this study was to determine if nasal colonization of pigs with a non-ST398 strain of MRSA could be reproduced using intra-nasal inoculation and to investigate subsequent transmission of this strain. Six pigs were inoculated intra-nasally with 2 x 109cfu MRSA t002. Six days post-inoculation these pigs were washed and moved to a clean house with 15 unexposed pigs (In-contact group). Another 15 unexposed pigs were added to the vacated house (Environment group)

    Dynamic Control of Laser Produced Proton Beams

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    The emission characteristics of intense laser driven protons are controlled using ultra-strong (of the order of 10^9 V/m) electrostatic fields varying on a few ps timescale. The field structures are achieved by exploiting the high potential of the target (reaching multi-MV during the laser interaction). Suitably shaped targets result in a reduction in the proton beam divergence, and hence an increase in proton flux while preserving the high beam quality. The peak focusing power and its temporal variation are shown to depend on the target characteristics, allowing for the collimation of the inherently highly divergent beam and the design of achromatic electrostatic lenses.Comment: 9 Pages, 5 figure

    A KRT71 Loss-of-Function Variant Results in Inner Root Sheath Dysplasia and Recessive Congenital Hypotrichosis of Hereford Cattle

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    Genodermatoses, such as heritable skin disorders, mostly represent Mendelian conditions. Congenital hypotrichosis (HY) characterize a condition of being born with less hair than normal. The purpose of this study was to characterize the clinicopathological phenotype of a breed-specific non-syndromic form of HY in Hereford cattle and to identify the causative genetic variant for this recessive disorder. Affected calves showed a very short, fine, wooly, kinky and curly coat over all parts of the body, with a major expression in the ears, the inner part of the limbs, and in the thoracic-abdominal region. Histopathology showed a severely altered morphology of the inner root sheath (IRS) of the hair follicle with abnormal Huxley and Henle’s layers and severely dysplastic hair shafts. A genome-wide association study revealed an association signal on chromosome 5. Homozygosity mapping in a subset of cases refined the HY locus to a 690 kb critical interval encompassing a cluster of type II keratin encoding genes. Protein-coding exons of six positional candidate genes with known hair or hair follicle function were re-sequenced. This revealed a protein-changing variant in the KRT71 gene that encodes a type II keratin specifically expressed in the IRS of the hair follicle (c.281delTGTGCCCA; p.Met94AsnfsX14). Besides obvious phenocopies, a perfect concordance between the presence of this most likely pathogenic loss-of-function variant located in the head domain of KRT71 and the HY phenotype was found. This recessive KRT71-related form of hypotrichosis provides a novel large animal model for similar human conditions. The results have been incorporated in the Online Mendelian Inheritance in Animals (OMIA) database (OMIA 002114-9913)

    Predicting intraurban airborne PM1.0-trace elements in a port city : Land use regression by ordinary least squares and a machine learning algorithm

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    Airborne particulate matter (PM) has been associated with cardiovascular and respiratory morbidity and mortality, and there is some evidence that spatially varying metals found in PM may contribute to adverse health effects. We developed spatially refined models for PM trace elements using ordinary least squares land use regression (OLS-LUR) and machine leaning random forest land-use regression (RF-LUR). Two-week integrated measurements of PM1.0 (median aerodiameter < 1.0 ÎĽm) were collected at 50 sampling sites during fall (2010), winter (2011), and summer (2011) in the Halifax Regional Municipality, Nova Scotia, Canada. PM1.0 filters were analyzed for metals and trace elements using inductively coupled plasma-mass spectrometry. OLS- and RF-LUR models were developed for approximately 30 PM1.0 trace elements in each season. Model predictors included industrial, commercial, and institutional/ government/ military land use, roadways, shipping, other transportation sources, and wind rose information. RF generated more accurate models than OLS for most trace elements based on 5-fold cross validation. On average, summer models had the highest cross validation R2 (OLS-LUR = 0.40, RF-LUR = 0.46), while fall had the lowest (OLS-LUR = 0.27, RF-LUR = 0.31). Many OLS-LUR models displayed overprediction in the final exposure surface. In contrast, RF-LUR models did not exhibit overpredictions. Taking overpredictions and cross validation performances into account, OLS-LUR performed better than RF-LUR in roughly 20% of the seasonal trace element models. RF-LUR models provided more interpretable predictors in most cases. Seasonal predictors varied, likely due to differences in seasonal distribution of trace elements related to source activity, and meteorology

    Violent video games and morality: a meta-ethical approach

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    This paper considers what it is about violent video games that leads one reasonably minded person to declare "That is immoral" while another denies it. Three interpretations of video game content a re discussed: reductionist, narrow, and broad. It is argued that a broad interpretation is required for a moral objection to be justified. It is further argued that understanding the meaning of moral utterances – like "x is immoral" – is important to an understanding of why there is a lack of moral consensus when it comes to the content of violent video games. Constructive ecumenical expressivism is presented as a means of explaining what it is that we are doing when we make moral pronouncements and why, when it comes to video game content, differing moral attitudes abound. Constructive ecumenical expressivism is also presented as a means of illuminating what would be required for moral consensus to be achieved

    European Medicines Agency review of ixazomib (Ninlaro) for the treatment of adult patients with multiple myeloma who have received at least one prior therapy

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    On 21 November 2016, the European Commission issued a marketing authorisation valid throughout the European Union for ixazomib in combination with lenalidomide and dexamethasone for the treatment of adult patients with multiple myeloma who have received at least one prior therapy. Ixazomib was evaluated in one, randomised, double-blind, phase III study comparing ixazomib plus lenalidomide and dexamethasone (n=360; ixazomib arm) versus placebo plus lenalidomide and dexamethasone (n=362; placebo arm) in adult patients with relapsed and/or refractory multiple myeloma who had received at least one prior therapy. The median progression-free survival (PFS) in the intent-to-treat population was 20.6 months in patients treated with ixazomib compared with 14.7 months for patients in the placebo arm (stratified HR=0.742, 95% CI 0.587 to 0.939, stratified p-value=0.012). The most frequently reported adverse reactions (≥20%) within the ixazomib and placebo arms were diarrhoea (42% vs 36%), constipation (34% vs 25%), thrombocytopaenia (28% vs 14%), peripheral neuropathy (28% vs 21%), nausea (26% vs 21%), peripheral oedema (25% vs 18%), vomiting (22% vs 11%) and back pain (21% vs 16%). The scientific review concluded that the gain in PFS of 5.9 months observed with ixazomib was considered clinically meaningful. Concerning the possible uncertainty about the magnitude of the effect, this uncertainty was acceptable given the favourable toxicity profile, and considering that ixazomib is the first agent to allow oral triple combination therapy in this patient population which represents a therapeutic innovation in terms of convenience for patients. Therefore, the benefit-risk for ixazomib in combination with lenalidomide and dexamethasone was considered positive, although the efficacy evidence was not as comprehensive as normally required

    Institutional repositories and the institutional repository.

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    This article reports on the archival implications of the 2006 Census of Institutional Repositories in the United States1 and follow-up interviews with the developers of institutional repositories in selected colleges and universities. The findings indicate that archivists generally play a quiet but persistent role in institutional repositories, and archival and special collections materials are a major source of content in institutional repositories. Institutional repositories (IRs) are becoming an extension of the institutional repository (archives). Still, a great deal of uncertainty surrounds preservation in IRs, and a potential, albeit currently unfilled, role for the archivist exists in providing digital preservation expertise for the IR.Institute of Museum and Library Services (IMLS)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106421/1/Yakel_American_Archivist_IRs.pd
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