Optimality Clue for Graph Coloring Problem

In this paper, we present a new approach which qualifies or not a solution found by a heuristic as a potential optimal solution. Our approach is based on the following observation: for a minimization problem, the number of admissible solutions decreases with the value of the objective function. For the Graph Coloring Problem (GCP), we confirm this observation and present a new way to prove optimality. This proof is based on the counting of the number of different k-colorings and the number of independent sets of a given graph G. Exact solutions counting problems are difficult problems (\#P-complete). However, we show that, using only randomized heuristics, it is possible to define an estimation of the upper bound of the number of k-colorings. This estimate has been calibrated on a large benchmark of graph instances for which the exact number of optimal k-colorings is known. Our approach, called optimality clue, build a sample of k-colorings of a given graph by running many times one randomized heuristic on the same graph instance. We use the evolutionary algorithm HEAD [Moalic et Gondran, 2018], which is one of the most efficient heuristic for GCP. Optimality clue matches with the standard definition of optimality on a wide number of instances of DIMACS and RBCII benchmarks where the optimality is known. Then, we show the clue of optimality for another set of graph instances. Optimality Metaheuristics Near-optimal

Detecting and Studying Higgs Bosons at a Photon-Photon Collider

We examine the potential for detecting and studying Higgs bosons at a photon-photon collider facility associated with a future linear collider. Our study incorporates realistic \gam\gam luminosity spectra based on the most probable available laser technology. Results include detector simulations. We study the cases of: a) a SM-like Higgs boson; b) the heavy MSSM Higgs bosons; c) a Higgs boson with no $WW/ZZ$ couplings from a general two Higgs doublet model.Comment: 52 pages, 26 figures, revised version with new appendi

The Higgs - photon - Z boson coupling revisited

We analyze the coupling of CP-even and CP-odd Higgs bosons to a photon and a Z boson in extensions of the Standard Model. In particular, we study in detail the effect of charged Higgs bosons in two-Higgs doublet models, and the contribution of SUSY particle loops in the minimal supersymmetric extension of the Standard Model. The Higgs-$\gamma Z$ coupling can be measured in the decay $Z \to \gamma$+Higgs at $e^+e^-$ colliders running on the Z resonance, or in the reverse process Higgs $\to Z \gamma$ with the Higgs boson produced at LHC. We show that a measurement of this coupling with a precision at the percent level, which could be the case at future $e^+e^-$ colliders, would allow to distinguish between the lightest SUSY and standard Higgs bosons in large areas of the parameter space.Comment: 18 pages LaTex + 7 figures (ps). Typo corrected in eq.(5

An improved method for statistical studies of the internal kinematics of HII regions: the case of M 83

We present the integrated Halpha emission line profile for 157 HII regions in the central 3.4' x 3.4' of the galaxy M 83 (NGC 5236). Using the Fabry-Perot interferometer GHaFaS, on the 4.2 m William Herschel on La Palma, we show the importance of a good characterization of the instrumental response function for the study of line profile shapes. The luminosity-velocity dispersion relation is also studied, and in the log(L)-log(sigma) plane we do not find a linear relation, but an upper envelope with equation log(L)=0.9 *log(sigma)+38.1. For the adopted distance of 4.5 Mpc, the upper envelope appears at the luminosity L=10^38.5 ergs, in full agreement with previous studies of other galaxies, reinforcing the idea of using HII regions as standard candles.Comment: 13 pages, 9 figures, accepted for publication in MNRA

Supersymmetry Relations Between Contributions To One-Loop Gauge Boson Amplitudes

We apply ideas motivated by string theory to improve the calculational efficiency of one-loop weak interaction processes with massive external gauge bosons. In certain cases ``supersymmetry'' relations between diagrams with a fermion loop and with a gauge boson loop hold. This is explicitly illustrated for a particular one-loop standard model process with four-external gauge bosons. The supersymmetry relations can be used to provide further significant improvements in calculational efficiency.Comment: 21 pages of plain TeX + 5 PostScript figures (compressed and uuencoded), UCLA/93/TEP/36 and DTP/93/8

H-alpha Kinematics of the SINGS Nearby Galaxies Survey. II

This is the second part of an H-alpha kinematics follow-up survey of the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample. The aim of this program is to shed new light on the role of baryons and their kinematics and on the dark/luminous matter relation in the star forming regions of galaxies, in relation with studies at other wavelengths. The data for 37 galaxies are presented. The observations were made using Fabry-Perot interferometry with the photon-counting camera FaNTOmM on 4 different telescopes, namely the Canada-France-Hawaii 3.6m, the ESO La Silla 3.6m, the William Herschel 4.2m, and the Observatoire du mont Megantic 1.6m telescopes. The velocity fields are computed using custom IDL routines designed for an optimal use of the data. The kinematical parameters and rotation curves are derived using the GIPSY software. It is shown that non-circular motions associated with galactic bars affect the kinematical parameters fitting and the velocity gradient of the rotation curves. This leads to incorrect determinations of the baryonic and dark matter distributions in the mass models derived from those rotation curves.Comment: 18 pages, 5 figures, 4 tables. Accepted for publication in MNRAS. All high-res. figures are available at http://www.astro.umontreal.ca/fantomm/singsII

The Search for Higgs particles at high-energy colliders: Past, Present and Future

I briefly review the Higgs sector in the Standard Model and its minimal Supersymmetric extension, the MSSM. After summarizing the properties of the Higgs bosons and the present experimental constraints, I will discuss the prospects for discovering these particle at the upgraded Tevatron, the LHC and a high-energy $e^+e^-$ linear collider. The possibility of studying the properties of the Higgs particles will be then summarized.Comment: 28 pages, latex, 15 figures, talk at WHEPP VII, Allahabad, Indi

Interacting mindreaders

Could interacting mindreaders be in a position to know things which they would be unable to know if they were manifestly passive observers? This paper argues that they could. Mindreading is sometimes reciprocal: the mindreader's target reciprocates by taking the mindreader as a target for mindreading. The paper explains how such reciprocity can significantly narrow the range of possible interpretations of behaviour where mindreaders are, or appear to be, in a position to interact. A consequence is that revisions and extensions are needed to standard theories of the evidential basis of mindreading. The view also has consequences for understanding how abilities to interact combined with comparatively simple forms of mindreading may explain the emergence, in evolution or development, of sophisticated forms of social cognition

Prisoners co-infected with tuberculosis and HIV: a systematic review.

INTRODUCTION: Almost from the beginning of the HIV epidemic in 1981, an association with tuberculosis (TB) was recognized. This association between HIV and TB co-infection has been particularly evident amongst prisoners. However, despite this, few studies of TB in prisons have stratified results by HIV status. Given the high prevalence of HIV-positive persons and TB-infected persons in prisons and the documented risk of TB in those infected with HIV, it is of interest to determine how co-infection varies amongst prison populations worldwide. For this reason we have undertaken a systematic review of studies of co-infected prisoners to determine the incidence and/or prevalence of HIV/TB co-infection in prisons, as well as outcomes in this group, measured as treatment success or death. METHODS: A literature search was undertaken using the online databases PubMed, Embase, IBSS, Scopus, Web of Science, Global Health and CINAHL Plus. No restrictions were set on language or publication date for article retrieval, with articles included if indexed up to 18 October 2015. A total of 1975 non-duplicate papers were identified. For treatment and outcome data all eligible papers were appraised for inclusion; for incidence/prevalence estimates papers published prior to 2000 were excluded from full text review. After full text appraisal, 46 papers were selected for inclusion in the review, 41 for incidence/prevalence estimates and nine for outcomes data, with four papers providing evidence for both outcomes and prevalence/incidence. RESULTS: Very few studies estimated the incidence of TB in HIV positive prisoners, with most simply reporting prevalence of co-infection. Co-infection is rarely explicitly measured, with studies simply reporting HIV status in prisoners with TB, or a cross-sectional survey of TB prevalence amongst prisoners with HIV. Estimates of co-infection prevalence ranged from 2.4 to 73.1% and relative risks for one, given the other, ranged from 2.0 to 10.75, although some studies reported no significant association between HIV and TB. Few studies provided a comparison with the risk of co-infection in the general population. CONCLUSIONS: Prisoners infected with HIV are at high risk of developing TB. However, the magnitude of risk varies between different prisons and countries. There is little evidence on treatment outcomes in co-infected prisoners, and the existing evidence is conflicting in regards to HIV status influence on prisoner treatment outcomes.PROSPERO Number: CRD42016034068