195 research outputs found

    3D Face Recognition with Sparse Spherical Representations

    Get PDF
    This paper addresses the problem of 3D face recognition using simultaneous sparse approximations on the sphere. The 3D face point clouds are first aligned with a novel and fully automated registration process. They are then represented as signals on the 2D sphere in order to preserve depth and geometry information. Next, we implement a dimensionality reduction process with simultaneous sparse approximations and subspace projection. It permits to represent each 3D face by only a few spherical functions that are able to capture the salient facial characteristics, and hence to preserve the discriminant facial information. We eventually perform recognition by effective matching in the reduced space, where Linear Discriminant Analysis can be further activated for improved recognition performance. The 3D face recognition algorithm is evaluated on the FRGC v.1.0 data set, where it is shown to outperform classical state-of-the-art solutions that work with depth images

    Novel phylogenetic algorithm to monitor human tropism in Egyptian H5N1-HPAIV reveals evolution toward efficient human-to-human transmission

    Get PDF
    Years of endemic infections with highly pathogenic avian influenza (HPAI) A subtype H5N1 virus in poultry and high numbers of infections in humans provide ample opportunity in Egypt for H5N1-HPAIV to develop pandemic potential. In an effort to better understand the viral determinants that facilitate human infections of the Egyptian H5N1-HPAIVvirus, we developed a new phylogenetic algorithm based on a new distance measure derived from the informational spectrum method (ISM). This new approach, which describes functional aspects of the evolution of the hemagglutinin subunit 1 (HA1), revealed a growing group G2 of H5N1-HPAIV in Egypt after 2009 that acquired new informational spectrum (IS) properties suggestive of an increased human tropism and pandemic potential. While in 2006 all viruses in Egypt belonged to the G1 group, by 2011 these viruses were virtually replaced by G2 viruses. All of the G2 viruses displayed four characteristic mutations (D43N, S120(D,N), (S,L)129Δ and I151T), three of which were previously reported to increase binding to the human receptor. Already in 2006–2008 G2 viruses were significantly (p<0.02) more often found in humans than expected from their overall prevalence and this further increased in 2009–2011 (p<0.007). Our approach also identified viruses that acquired additional mutations that we predict to further enhance their human tropism. The extensive evolution of Egyptian H5N1-HPAIV towards a preferential human tropism underlines an urgent need to closely monitor these viruses with respect to molecular determinants of virulence

    Evaluation of patient STress level caused by radiological Investigations in early Postoperative phase After CRANIOtomy (IPAST-CRANIO): protocol of a Swiss prospective cohort study

    Full text link
    INTRODUCTION Postoperative imaging after neurosurgical interventions is usually performed in the first 72 hours after surgery to provide an accurate assessment of postoperative resection status. Patient frequently report that early postoperative examination after craniotomy for tumour and vascular procedures is associated with distress, exertion, nausea and pain. Delayed postoperative imaging (between 36 and 72 hours postoperatively) may have an advantage regarding psychological and physical stress compared with early imaging. The goal of this study is to evaluate and determine the optimal time frame for postoperative imaging with MRI and CT in terms of medical and neuroradiological implications and patient's subjective stress level. METHODS AND ANALYSIS Data will be prospectively collected from all patients aged 18-80 years who receive postoperative MRI or CT imaging following a craniotomy for resection of a cerebral tumour (benign and malignant) or vascular surgery. Participants have to complete questionnaires containing visual analogue scores (VAS) for headache and nausea, Body Part Discomfort score and a single question addressing subjective preference of timing of postoperative imaging after craniotomy. The primary endpoint of the study is the difference in subjective stress due to imaging studies after craniotomy, measured just before and after postoperative MRI or CT with the above-mentioned instruments. Subjective stress is defined as a combination of the scores VAS pain, VAS nausea and 0.5* Body Part Discomfort core.This study determines whether proper timing of postoperative imaging can improve patient satisfaction and reduce pain, stress and discomfort caused by postoperative imaging. Factors causing additional postoperative stress are likely responsible for delayed recovery of neurosurgical patients. ETHICS AND DISSEMINATION The institutional review board (Kantonale Ethikkommission ZĂŒrich) approved this study on 4 August 2020 under case number BASEC 2020-01590. The authors are planning to publish the data of this study in a peer-reviewed paper. After database closure, the data will be exported to the local data repository (Zurich Open Repository and Archive) of the University of Zurich. The sponsor (LR) and the project leader (MR.G) will make the final decision on the publication of the results. The data that support the findings of this study are available on request from the corresponding author LT. The data are not publicly available due to privacy/ethical restrictions. TRIAL REGISTRATION NUMBER NCT05112575; ClinicalTrials.gov

    Cylindrical quantum wires with hydrogen-bonded materials

    Full text link
    Properties of cylindrical quantum wires are analysed in this paper. Energies of elementary excitations as well as one-particle wave functions were found for mentioned structure. For cylindrical quantum wires the temperature of phase transition was found. The behaviour of electric susceptibility in paraelectric phase was investigated.Comment: 10 page

    GRAPH-THEORETICAL STUDIES ON FLUORANTHENOIDS AND FLUORENOIDS - ENUMERATION OF SOME CATACONDENSED SYSTEMS

    Get PDF
    Precise definitions are given for some classes of molecular graphs with one pentagon and otherwise hexagons: the monopentapolyhexes. The fluoranthenoid and fluorenoid systems belong to monopentapolyhexes. Complete mathematical solutions, using combinatorial summations on the one hand and generating functions on the other hand, are given for the numbers of catacondensed simply connected monopentapolyhexes (catafluorenoids and the corresponding helicenic systems). Generating functions and numerical values are included

    Electron-impact excitation of the (4d(10)5s) S-2(1/2)-> (4d(9)5s(2)) D-2(3/2) and (4d(10)6s) S-2(1/2) ->(4d(10)6s) 2S(1/ 2) transitions in silver: Experiment and theory

    Get PDF
    We present angle-differential and angle-integrated cross sections for electron-impact excitation of the (4d(10)5s) S-2(1/ 2) -> (4d(9)5s(2)) D-2(3/ 2) and (4d(10)5s) S-2(1/ 2) ->(4d(10)6s) S-2(1/ 2) transitions in atomic silver. Experimental data for four incident electron energies between 10 and 60 eV are compared with predictions from our relativistic distorted wave (RDW) and nonrelativistic atomic optical potential models. Agreement between our measured and calculated data is only fair, although in the case of the RDW it is seen to improve with increasing incident electron energy. However, only for the (4d(10)6s) S-2(1/2) excitation process, agreement of our measured data with earlier relativistic convergent close coupling results from McNamara et al. [J. Phys. B 51, 085203 (2018)] was, with a few exceptions, typically observed to be very good, to within the uncertainties on the data

    Discriminative Localized Sparse Representations for Breast Cancer Screening

    Full text link
    Breast cancer is the most common cancer among women both in developed and developing countries. Early detection and diagnosis of breast cancer may reduce its mortality and improve the quality of life. Computer-aided detection (CADx) and computer-aided diagnosis (CAD) techniques have shown promise for reducing the burden of human expert reading and improve the accuracy and reproducibility of results. Sparse analysis techniques have produced relevant results for representing and recognizing imaging patterns. In this work we propose a method for Label Consistent Spatially Localized Ensemble Sparse Analysis (LC-SLESA). In this work we apply dictionary learning to our block based sparse analysis method to classify breast lesions as benign or malignant. The performance of our method in conjunction with LC-KSVD dictionary learning is evaluated using 10-, 20-, and 30-fold cross validation on the MIAS dataset. Our results indicate that the proposed sparse analyses may be a useful component for breast cancer screening applications

    Clinical significance of genetic aberrations in secondary acute myeloid leukemia

    Get PDF
    The study aimed to identify genetic lesions associated with secondary acute myeloid leukemia (sAML) in comparison with AML arising de novo (dnAML) and assess their impact on patients' overall survival (OS). High-resolution genotyping and loss of heterozygosity mapping was performed on DNA samples from 86 sAML and 117 dnAML patients, using Affymetrix Genome-Wide Human SNP 6.0 arrays. Genes TP53, RUNX1, CBL, IDH1/2, NRAS, NPM1, and FLT3 were analyzed for mutations in all patients. We identified 36 recurrent cytogenetic aberrations (more than five events). Mutations in TP53, 9pUPD, and del7q (targeting CUX1 locus) were significantly associated with sAML, while NPM1 and FLT3 mutations associated with dnAML. Patients with sAML carrying TP53 mutations demonstrated lower 1-year OS rate than those with wild-type TP53 (14.3% +/- 9.4% vs. 35.4% +/- 7.2%; P = 0.002), while complex karyotype, del7q (CUX1) and del7p (IKZF1) showed no significant effect on OS. Multivariate analysis confirmed that mutant TP53 was the only independent adverse prognostic factor for OS in sAML (hazard ratio 2.67; 95% CI: 1.335.37; P = 0.006). Patients with dnAML and complex karyotype carried sAML-associated defects (TP53 defects in 54.5%, deletions targeting FOXP1 and ETV6 loci in 45.4% of the cases). We identified several co-occurring lesions associated with either sAML or dnAML diagnosis. Our data suggest that distinct genetic lesions drive leukemogenesis in sAML. High karyotype complexity of sAML patients does not influence OS. Somatic mutations in TP53 are the only independent adverse prognostic factor in sAML. Patients with dnAML and complex karyotype show genetic features associated with sAML and myeloproliferative neoplasms. Am. J. Hematol., 2012

    From Davydov solitons to decoherence-free subspaces: self-consistent propagation of coherent-product states

    Get PDF
    The self-consistent propagation of generalized D1D_{1} [coherent-product] states and of a class of gaussian density matrix generalizations is examined, at both zero and finite-temperature, for arbitrary interactions between the localized lattice (electronic or vibronic) excitations and the phonon modes. It is shown that in all legitimate cases, the evolution of D1D_{1} states reduces to the disentangled evolution of the component D2D_{2} states. The self-consistency conditions for the latter amount to conditions for decoherence-free propagation, which complement the D2D_{2} Davydov soliton equations in such a way as to lift the nonlinearity of the evolution for the on-site degrees of freedom. Although it cannot support Davydov solitons, the coherent-product ansatz does provide a wide class of exact density-matrix solutions for the joint evolution of the lattice and phonon bath in compatible systems. Included are solutions for initial states given as a product of a [largely arbitrary] lattice state and a thermal equilibrium state of the phonons. It is also shown that external pumping can produce self-consistent Frohlich-like effects. A few sample cases of coherent, albeit not solitonic, propagation are briefly discussed.Comment: revtex3, latex2e; 22 pages, no figs.; to appear in Phys.Rev.E (Nov.2001
    • 

    corecore