Characterizing Width Uniformity by Wave Propagation

This work describes a novel image analysis approach to characterize the uniformity of objects in agglomerates by using the propagation of normal wavefronts. The problem of width uniformity is discussed and its importance for the characterization of composite structures normally found in physics and biology highlighted. The methodology involves identifying each cluster (i.e. connected component) of interest, which can correspond to objects or voids, and estimating the respective medial axes by using a recently proposed wavefront propagation approach, which is briefly reviewed. The distance values along such axes are identified and their mean and standard deviation values obtained. As illustrated with respect to synthetic and real objects (in vitro cultures of neuronal cells), the combined use of these two features provide a powerful description of the uniformity of the separation between the objects, presenting potential for several applications in material sciences and biology.Comment: 14 pages, 23 figures, 1 table, 1 referenc

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

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

New Results in Sasaki-Einstein Geometry

This article is a summary of some of the author's work on Sasaki-Einstein geometry. A rather general conjecture in string theory known as the AdS/CFT correspondence relates Sasaki-Einstein geometry, in low dimensions, to superconformal field theory; properties of the latter are therefore reflected in the former, and vice versa. Despite this physical motivation, many recent results are of independent geometrical interest, and are described here in purely mathematical terms: explicit constructions of infinite families of both quasi-regular and irregular Sasaki-Einstein metrics; toric Sasakian geometry; an extremal problem that determines the Reeb vector field for, and hence also the volume of, a Sasaki-Einstein manifold; and finally, obstructions to the existence of Sasaki-Einstein metrics. Some of these results also provide new insights into Kahler geometry, and in particular new obstructions to the existence of Kahler-Einstein metrics on Fano orbifolds.Comment: 31 pages, no figures. Invited contribution to the proceedings of the conference "Riemannian Topology: Geometric Structures on Manifolds"; minor typos corrected, reference added; published version; Riemannian Topology and Geometric Structures on Manifolds (Progress in Mathematics), Birkhauser (Nov 2008

Momentum scale calibration of the LHCb spectrometer

For accurate determination of particle masses accurate knowledge of the momentum scale of the detectors is crucial. The procedure used to calibrate the momentum scale of the LHCb spectrometer is described and illustrated using the performance obtained with an integrated luminosity of 1.6 fb-1 collected during 2016 in pp running. The procedure uses large samples of J/ψ → μ + μ - and B+ → J/ψ K + decays and leads to a relative accuracy of 3 × 10-4 on the momentum scale

Curvature-bias corrections using a pseudomass method

Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy √(s)=13 TeV during 2016, 2017 and 2018. The biases are determined using Z→μ + μ - decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10-4 GeV-1 level, improves the Z→μ + μ - mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass

Measurement of CP asymmetries and branching fraction ratios of B− decays to two charm mesons

The $CP$ asymmetries of seven $B^-$ decays to two charm mesons are measured using data corresponding to an integrated luminosity of $9\text{fb}^{-1}$ of proton-proton collisions collected by the LHCb experiment. Decays involving a $D^{*0}$ or $D^{*-}_s$ meson are analysed by reconstructing only the $D^0$ or $D^-_s$ decay products. This paper presents the first measurement of $\mathcal{A}^{CP}(B^- \rightarrow D^{*-}_s D^0)$ and $\mathcal{A}^{CP}(B^- \rightarrow D^{-}_s D^{*0})$, and the most precise measurement of the other five $CP$ asymmetries. There is no evidence of $CP$ violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured.The CP asymmetries of seven B$^{−}$ decays to two charm mesons are measured using data corresponding to an integrated luminosity of 9 fb$^{−1}$ of proton-proton collisions collected by the LHCb experiment. Decays involving a D$^{*0}$ or ${D}_s^{\ast -}$ meson are analysed by reconstructing only the D$^{0}$ or ${D}_s^{-}$ decay products. This paper presents the first measurement of $\mathcal{A} ^{CP}$(B$^{−}$→${D}_s^{\ast -}$D$^{0}$) and $\mathcal{A} ^{CP}$(B$^{−}$→${D}_s^{-}$D$^{∗0}$), and the most precise measurement of the other five CP asymmetries. There is no evidence of CP violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured.[graphic not available: see fulltext]The $CP$ asymmetries of seven $B^-$ decays to two charm mesons are measured using data corresponding to an integrated luminosity of $9\text{ fb}^{-1}$ of proton-proton collisions collected by the LHCb experiment. Decays involving a $D^{*0}$ or $D^{*-}_s$ meson are analysed by reconstructing only the $D^0$ or $D^-_s$ decay products. This paper presents the first measurement of $\mathcal{A}^{CP}(B^- \rightarrow D^{*-}_s D^0)$ and $\mathcal{A}^{CP}(B^- \rightarrow D^{-}_s D^{*0})$, and the most precise measurement of the other five $CP$ asymmetries. There is no evidence of $CP$ violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured

Helium identification with LHCb

The identification of helium nuclei at LHCb is achieved using a method based on measurements of ionisation losses in the silicon sensors and timing measurements in the Outer Tracker drift tubes. The background from photon conversions is reduced using the RICH detectors and an isolation requirement. The method is developed using pp collision data at √(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, corresponding to an integrated luminosity of 5.5 fb-1. A total of around 105 helium and antihelium candidates are identified with negligible background contamination. The helium identification efficiency is estimated to be approximately 50% with a corresponding background rejection rate of up to O(10^12). These results demonstrate the feasibility of a rich programme of measurements of QCD and astrophysics interest involving light nuclei

Optimum Path Forest Classifier Applied To Laryngeal Pathology Detection

Optimum path forest-based classifiers are a novel approach for supervised pattern recognition. The OPF classifier differs from traditional approaches by not estimating probability density functions of the classes neither assuming samples linearity, and creates a discrete optimal partition of the feature space, in which the decision boundary is obtained by the influence zones of the most representative samples of the training set. Due to the large number of applications in biomedical signal processing involving pattern recognition techniques, specially voice disorders identification, we propose here the laryngeal pathology detection by means of OPF. Experiments were performed in three public datasets against SVM, and a comparison in terms of accuracy rates and execution times was also regarded.249252A.A. Spadotto, J.P. Papa, A.R. Gatto, P.C. Cola, J.C. Pereira, R.C. Guido, and A.O. Schelp, Denoising swallowing sound to improve the evaluators qualitative analysis., Computers and Electrical Engineering: Advances on Computer-based Biological Signal Processing Techniques, 34, no. 2, pp. 148-153, 2008Spadotto, A.A., Pereira, J.C., Guido, R.C., Papa, J.P., Falcão, A.X., Gatto, A.R., Cola, P.C., Shelp, A.O., Oropharyngeal dysphagia identification using wavelets and optimum path forest (2008) Proceedings of the 3th IEEE International Symposium on Communications, Control and Signal Processing, , to appearHadjitodorov, S.T., Boyanov, B., Teston, B., Laryngeal pathology detection by means of class-specific neural maps (2000) IEEE Transactions on Information Technology in Biomedicine, 4 (1), pp. 68-73Boyanov, B., Hadjitodorov, S.T., Acoustic analysis of pathological voices. a voice analysis systemfor the screening of laryngeal diseases (1997) IEEE Transactions on Engineering in Medicine and Biology Magazine, 16 (4), pp. 74-82Godino-Llorente, J.I., Vilda, P.G., Senz-Lechn, N., Blanco-Velasco, M., Craz-Roldn, F., Ferrer-Ballester, M.A., (2005) Support vector machines applied to the detection of voice disorders, 3817, pp. 219-230Perrin, E., Berger-Vachon, C., Kauffmann, I., Collet, L., (2006) Acoustical recognition of laryngeal pathology using the fundamental frequency and the first three formants of vowels, 35 (4), pp. 361-368Mezzalama, M., Prinetto, P., Morra, B., (2006) Experiments in automatic classification of laryngeal pathology, 21 (5), pp. 603-611Hadjitodorov, S.T., Ivanov, T., Boyanov, B., Analysis of dysphony using objective voice parameter (1993) Proceedings of the II Balkan Conference on Operational Research, pp. 911-917Schlotthauer, G., Torres, M.E., Jackson-Menaldi, C., Automatic diagnosis of pathological voices (2006) Proceedings of the 6th WSEAS International Conference on Signal, Speech and Image Processing, pp. 150-155Boser, B.E., Guyon, I.M., Vapnik, V.N., A training algorithm for-optimal margin classifiers (1992) Proc. 5th Workshop on Computational Learning Theory, pp. 144-152. , New York, NY, USA, ACM PressDuan, K., Keerthi, S.S., Which is the best multiclass svm method? an empirical study (2005) Multiple Classifier Systems, pp. 278-285Papa, J.P., Falcão, A.X., Miranda, P.A.V., Suzuki, C.T.N., Mascarenhas, N.D.A., Design of robust pattern classifiers based on optimum-path forests (2007) Mathematical Morphology and its Applications to Signal and Image Processing (ISMM), pp. 337-348. , MCT/INPEPapa, J.P., Falcão, A.X., Suzuki, C.T.N., Mascarenhas, N.D.A., A discrete approach for supervised pattern recognition (2008) 12th International Workshop on Combinatorial Image Analysis (IWCIA), 4958, pp. 136-147. , SpringerJ.A. Montoya-Zegarra, J.P. Papa, N.J. Leite, R.S. Torres, and A.X. Falcão, Rotation-invariant texture recognition, in 3rd International Symposium on Visual Computing, Lake Tahoe, Nevada, CA, USA, Nov 2007, Part II, LNCS 4842, pp. 193-204, SpringerFalcão, A.X., Stolfi, J., Lotufo, R.A., The image foresting transform: Theory, algorithms, and applications (2004) IEEE Trans. on PAMI, 26 (1), pp. 19-29. , JanAllène, C., Audibert, J.Y., Couprie, M., Cousty, J., Keriven, R., Some links between min-cuts, optimal spanning forests and watersheds (2007) Proceedings of the ISMM'08, pp. 253-264Hadjitodorov, S.T., Mitev, P., Boyanov, B., (2005) Laryngeal databases, , http://www.informatics.bangor.ac.uk/~kuncheva, Available inCohen, J., A coefficient of agreement for nominal scales (1960) Educational and Psychological Measurement, 20, pp. 37-46Chang, C.C., Lin, C.J., (2001) LIBSVM: A library for support vector machines, , http://www.csie.ntu.edu.tw/~cjlin/libsvm, Software available at ur

Oropharyngeal Dysphagia Identification Using Wavelets And Optimum Path Forest

The swallowing disturbers are defined as oropharyngeal dysphagia when present specifies signals and symptoms that are characterized for alterations in any phases of swallowing. Early diagnosis is crucial for the prognosis of patients with dysphagia and the potential to diagnose dysphagia in a noninvasive manner by assessing the sounds of swallowing is a highly attractive option for the dysphagia clinician. This study proposes a new framework for oropharyngeal dysphagia identification, having two main contributions: a new set of features extract from swallowing signal by discrete wavelet transform and the dysphagia classification by a novel pattern classifier called OPF. We also employed the well known SVM algorithm in the dysphagia identification task, for comparison purposes. We performed the experiments in two sub-signals: the first was the moment of the maximal peak (MP) of the signal and the second is the swallowing apnea period (SAP). The OPF final accuracy obtained were 85.2% and 80.2% for the analyzed signals MP and SAP, respectively, outperforming the SVM results. ©2008 IEEE.735740Logemann, J.A., (1983) Evaluation and treatment of swallowing disorders, , College- Hill PressPlatt, J., (2001) Dysphagia Management for Long-Term Care: A Manual for Nurses and Other Healthcare Professionals, Clinical and Educational ServicesFurkim, A.M., Silva, R.G., (1999) Programas de reabilitacão em disfagia neurogênica, , Frôntis EditorialChen, M.Y.M., Ott, D.J., Peele, V.N., Gelfand, D.W., Oropharynx in pacients with cerebrovascular disease: Evaluation with videofluoroscopy (1990) Radiology, 176, pp. 38-47J.B. Palmer and A.S. Duchane, Rehabilitation of swallowing disorders due to stroke, hys. Med. Rehab.Clin. N. Amer, 2, 1991Horner, J., Buoyer, F.G., Alberts, M.J., Helms, M.J., Dysphagia folowing brain stem stroke: Clinical correlates and outcome (1991) Arch Neurol, 48, pp. 1170-1173Buchhloz, D.W., (1997) Neurologic disordes of swallowing, pp. 37-62. , ppVeis, S.L., Logemann, J.A., Swallowing disorders in persons with cerebrovascular accident (1985) Arch Phys Med Rehabil, 66, pp. 372-376Gordon, C., Hewer, R.L., Wade, D.T., Dysphagia in acute stroke (1987) Brazilian Medical Journal, pp. 3411-3414Silva, R.G., Disfagia neurogênica em adultos: Uma proposta para avaliacão clínica (1999) Disfagias Orofaríngeas, pp. 35-47Cichero, J.A.Y., Murdoch, B.E., The physiologic cause of swallowing sounds: Answers from heart sounds and vocal tract acoustics (1998) Dysphagia, 13, pp. 39-52Youmans, S.R., Stierwalt, J.A.G., The physiologic cause of swallowing sounds: Answers from heart sounds and vocal tract acousticsan acoustic profile of normal swallowing (2005) Dysphagia, 20, pp. 195-209Lazareck, L.J., Moussavi, Z., Classification of normal and dysphagic swallows by acoustical means (2004) IEEE Transactions on Biomedical Engineering, 51Kuncheva, L.I., (2004) Combining Pattern Classifiers: Methods and Algorithms, , Wiley-InterscienceAboofazeli, M., Moussavi, Z., Automated extraction of swallowing sounds using a wavelet-based filter (2006) Engineering in Medicine and Biology Society, 2006. EMBS '06. 28th Annual International Conference of the IEEE, pp. 5607-5610Papa, J.P., Falcão, A.X., Miranda, P.A.V., Suzuki, C.T.N., Mascarenhas, N.D.A., Design of robust pattern classifiers based on pptimum-path forests (2007) Mathematical Morphology and its Applications to Signal and Image Processing (ISMM), pp. 337-348. , MCT/INPEPapa, J.P., Falcão, A.X., Suzuki, C.T.N., Mascarenhas, N.D.A., A discrete approach for supervised pattern recognition (2008) Proceedings of the 12th International Workshop on Combinatorial Image Analysis, , Accepted for publicationBoser, B.E., Guyon, I.M., Vapnik, V.N., A training algorithm for optimal margin classifiers (1992) Proc. 5th Workshop on Computational Learning Theory, pp. 144-152. , New York, NY, USA, ACM PressJ.A. Montoya-Zegarra, J.P. Papa, N.J. Leite, R.S. Torres, and A.X. Falcão, Rotation-invariant texture recognition, in 3rd International Symposium on Visual Computing, Lake Tahoe, Nevada, CA, USA, Nov 2007, Part II, LNCS 4842, pp. 193-204, SpringerVapnik, V.N., An overview of statistical learning theory (1999) Neural Networks, IEEE Transactions on, 10 (5), pp. 988-999Bazaraa, M.S., Sherali, H.D., Shetti, C.M., (2006) Nonlinear programming theory and algorithms, , Wiley-InterscienceBurges, C.J.C., A tutorial on support vector machines for pattern recognition (1998) Data Mining and Knowledge Discovery, 2 (2), pp. 121-167Falcão, A.X., Stolfi, J., Lotufo, R.A., The image foresting transform: Theory, algorithms, and applications (2004) IEEE Trans. on PAMI, 26 (1), pp. 19-29. , JanCormen, T., Leiserson, C., Rivest, R., (1990) Introduction to Algorithms, , MITAllène, C., Audibert, J.Y., Couprie, M., Cousty, J., Keriven, R., Some links between min-cuts, optimal spanning forests and watersheds (2007) Proceedings of the 8th Int. Symposium on Mathematical Morphology, pp. 253-264Addison, P.S., (2002), Institute of Physics Publishing Bristol and PhiladelphiaMallat, S.G., A theory for multiresolution signal decomposition: The wavelet representation (1989) IEEE Transactions on Pattern Analysis and Machine Intelligence, 11 (7), pp. 674-693Daubechies, I., The wavelet transform, time-frequency localization and signal analysis (1990) IEEE Transactions on Information Theory, 36 (5), pp. 961-1005I. Daubechies, Philadelphia, PA: Soc. Indus. Applied Math., 1992Daubechies, I., Orthonormal bases of compactly supported wavelets ii, variations on a theme (1993) SIAM J. Math. Anal, 24 (2), p. 499519Spadotto, A.A., Papa, J.P., Gatto, A.R., Cola, P.C., Pereira, J.C., Guido, R.C., Schelp, A.O., Denoising swallowing sound to improve the evaluators qualitative analysis (2007) Computers and Electrical Engineering, , accepted for publicationChang, C.C., Lin, C.J., (2001) LIBSVM: A library for support vector machines, , http://www.csie.ntu.edu.tw/~cjlin/libsvm, Software available at ur