1,486 research outputs found

    ShapeFit and ShapeKick for Robust, Scalable Structure from Motion

    Full text link
    We introduce a new method for location recovery from pair-wise directions that leverages an efficient convex program that comes with exact recovery guarantees, even in the presence of adversarial outliers. When pairwise directions represent scaled relative positions between pairs of views (estimated for instance with epipolar geometry) our method can be used for location recovery, that is the determination of relative pose up to a single unknown scale. For this task, our method yields performance comparable to the state-of-the-art with an order of magnitude speed-up. Our proposed numerical framework is flexible in that it accommodates other approaches to location recovery and can be used to speed up other methods. These properties are demonstrated by extensively testing against state-of-the-art methods for location recovery on 13 large, irregular collections of images of real scenes in addition to simulated data with ground truth

    Average-Case Optimal Approximate Circular String Matching

    Full text link
    Approximate string matching is the problem of finding all factors of a text t of length n that are at a distance at most k from a pattern x of length m. Approximate circular string matching is the problem of finding all factors of t that are at a distance at most k from x or from any of its rotations. In this article, we present a new algorithm for approximate circular string matching under the edit distance model with optimal average-case search time O(n(k + log m)/m). Optimal average-case search time can also be achieved by the algorithms for multiple approximate string matching (Fredriksson and Navarro, 2004) using x and its rotations as the set of multiple patterns. Here we reduce the preprocessing time and space requirements compared to that approach

    Pearson cross-correlation in the first four black hole binary mergers

    No full text
    We adopt the Pearson cross-correlation measure to analyze the LIGO Hanford and LIGO Livingston detector data streams around the events GW150914, GW151012,GW151226 and GW170104. We find that the Pearson cross-correlation method is sensitive to these signals, with correlations peaking when the black hole binaries reconstructed by the LIGO Scientific and Virgo Collaborations, are merging. We compare the obtained cross-correlations with the statistical correlation fluctuations arising in simulated Gaussian noise data and in LIGO data at times when no event is claimed. Our results for the significance of the observed cross-correlations are broadly consistent with those announced by the LIGO Scientific and Virgo Collaborations based on matched-filter analysis. In the same data, if we subtract the maximum likelihood waveforms corresponding to the announced signals, no residual cross-correlations persists at a statistically significant level

    Comparison of the biotypes of Yersinia enterocolitica isolated from pigs, cattle and sheep at slaughter and from humans with yersiniosis in Great Britain during 1999-2000

    Get PDF
    Aims: To investigate the relationship between livestock carriage of Yersinia enterocolitica and human disease. The biotypes/serotypes of strains recovered from the faeces of pigs, cattle and sheep at slaughter during a national survey in Great Britain in 1999-2000, were compared with those of strains isolated from human cases of yersiniosis during the same period. Methods and Results: The faecal carriage of Y. enterocolitica by cattle, sheep and pigs at slaughter was 6.3, 10.7 and 26.1%, respectively. Yersinia enterocolitica biotype (BT) 1a was the most frequently isolated biotype from livestock (58%) and was the predominant biotype (53%) isolated from human cases over the same period. The main recognized pathogenic Y. enterocolitica biotype isolated from livestock was BT3 (O:5,27) (35% of sheep, 22% of pigs and 4% of cattle) but this biotype was not detected in any of the human isolates investigated. The major pathogenic biotypes of strains isolated from humans were BT3 (O:9) (24%) and BT4 (O:3) (19%) whereas of the veterinary isolates investigated, only pigs (11%) carried BT3 (O:9) strains. Conclusions: Because of significant overlaps in phenotypes of the veterinary and human strains it is not possible to comment on the correlation between host and pathogenicity, especially of biotype 1a. Significance and Impact of the Study: The data suggest that further investigations using methods with greater discriminatory power are required. However the data also suggests that pigs may be the primary reservoir for human pathogenic Y. enterocolitica infection

    Can ICU admission be predicted?

    Get PDF
    After intensive care (IC), patients report poor health-related quality of life (HRQoL). Many factors affect the patients and influence the HRQoL after discharge. One of these factors is the patient's health status before the critical care period. In a previous study we found that the IC patients have a high frequency of pre-existing diseases. However, it is unknown to what extent these pre-existing diseases affect the consumption of hospital resources (measured as days as inpatients) in the time period before admission to the ICU and during the years following it. The consumption prior to the ICU event may also be claimed to herald an increased risk for a later ICU admittance? The aim of this study was to examine the hospital care consumption of former ICU patients 3 years prior to and 3 years after the intensive care period. This was examined in relation to the pre-existing health status

    Risk of ischemic heart disease after radiotherapy for ductal carcinoma in situ

    Get PDF
    The use of adjuvant radiotherapy (RT) in the management of ductal carcinoma in situ (DCIS) is increasing. Left-sided breast irradiation may involve exposure of the heart to ionising radiation, increasing the risk of ischemic heart disease (IHD). We examined the incidence of IHD in a population-based cohort of women with DCIS. The Breast Cancer DataBase Sweden (BCBase) cohort includes women registered with invasive and in situ breast cancers 1992-2012 and age-matched women without a history of breast cancer. In this analysis, 6270 women with DCIS and a comparison cohort of 31,257 women were included. Through linkage with population-based registers, data on comorbidity, socioeconomic status and incidence of IHD was obtained. Hazard ratios (HR) for IHD with 95% confidence intervals (CI) were analysed. Median follow-up time was 8.8 years. The risk of IHD was not increased for women with DCIS versus women in the comparison cohort (HR 0.93; 95% CI 0.82-1.06), after treatment with radiotherapy versus surgery alone (HR 0.77; 95% CI 0.60-0.98) or when analysing RT by laterality (HR 0.85; 95% CI 0.53-1.37 for left-sided versus right-sided RT). The risk of IHD was lower for women with DCIS allocated to RT compared to non-irradiated women and to the comparison cohort, probably due to patient selection. Comparison of RT by laterality did not show any over-risk for irradiation of the left breast.Peer reviewe

    Quark-diquark Systematics of Baryons: Spectral Integral Equations for Systems Composed by Light Quarks

    Full text link
    For baryons composed by the light quarks (q=u,dq=u,d) we write spectral integral equation using the notion of two diquarks: (i) axial--vector state, D11D^{1}_{1}, with the spin SD=1S_D=1 and isospin ID=1I_D=1 and (ii) scalar one, D00D^{0}_{0}, with the spin SD=0S_D=0 and isospin ID=0I_D=0. We present spectral integral equations for the qD00qD^{0}_{0} and qD11qD^{1}_{1} states taking into account quark--diquark confinement interaction.Comment: 13 pages, 2 figure

    Reflections and Experiences of a Co-Researcher involved in a Renal Research Study

    Get PDF
    Background Patient and Public Involvement (PPI) is seen as a prerequisite for health research. However, current Patient and public involvement literature has noted a paucity of recording of patient and public involvement within research studies. There have been calls for more recordings and reflections, specifically on impact. Renal medicine has also had similar criticisms and any reflections on patient and public involvement has usually been from the viewpoint of the researcher. Roles of patient and public involvement can vary greatly from sitting on an Advisory Group to analysing data. Different PPI roles have been described within studies; one being a co-researcher. However, the role of the co-researcher is largely undefined and appears to vary from study to study. Methods The aims of this paper are to share one first time co-researcher's reflections on the impact of PPI within a mixed methods (non-clinical trial) renal research study. A retrospective, reflective approach was taken using data available to the co-researcher as part of the day-to-day research activity. Electronic correspondence and documents such as meeting notes, minutes, interview thematic analysis and comments on documents were re-examined. The co-researcher led on writing this paper. Results This paper offers a broad definition of the role of the co-researcher. The co-researcher reflects on undertaking and leading on the thematic analysis of interview transcripts, something she had not previously done before. The co-researcher identified a number of key themes; the differences in time and responsibility between being a coresearcher and an Advisory Group member; how the role evolved and involvement activities could match the co-researchers strengths (and the need for flexibility); the need for training and support and lastly, the time commitment. It was also noted that it is preferable that a co-researcher needs to be involved from the very beginning of the grant application. Conclusions The reflections, voices and views of those undertaking PPI has been largely underrepresented in the literature. The role of co-researcher was seen to be rewarding but demanding, requiring a large time commitment. It is hoped that the learning from sharing this experience will encourage others to undertake this role, and encourage researchers to reflect on the needs of those involved.Peer reviewedFinal Published versio
    corecore