452 research outputs found
TooManyEyes: Super-recogniser directed identification of target individuals on CCTV
For the current research, a ‘Spot the Face in a Crowd Test’ (SFCT) comprising six video clips depicting target-actors and multiple bystanders was loaded on TooManyEyes, a bespoke multi-media platform adapted here for the human-directed identification of individuals in CCTV footage. To test the utility of TooManyEyes, police ‘super-recognisers’ (SRs) who may possess exceptional face recognition ability, and police controls attempted to identify the target-actors from the SFCT. As expected, SRs correctly identified more target-actors; with higher confidence than controls. As such, the TooManyEyes system provides a useful platform for uploading tests for selecting police or security staff for CCTV review deploymen
Facteurs predictifs de gravite des cellulites cervico-faciales diffuses d’origine dentaire : a propos de 78 cas
Introduction : La cellulite cervico-faciale est une dermohypodermite qui prend origine au niveau de la graisse hypodermique a partir d’effraction d'un foyer dentaire. Sa gravité réside d'une part dans sa forme diffuse avec risque d'obstruction des voies aériennes et de médiastinite et d'autre part dans sa forme nécrosante avec risque de fasciite nécrosante et de gangrène gazeuse. en l'absence de prise en charge multidisciplinaire et urgente, l'évolution de ces formes grave se fera vers le sepsis, le choc septique et le Syndrome de défaillance multi viscérales. L’objectif est de retrouver des facteurs prédictifs d'extension allant de l'atteinte des voies aériennes supérieures à l'infiltration médiastinale, ainsi que des facteurs prédictifs du type de cellulite (phlegmoneuse ou nécrotique).Patients et méthode : étude rétrospective faite sur une période de 7ans qui a permis d’exploiter 78 dossiers de cellulites cervico-faciales diffuses (CCFD) colligées au service d’OrL et chirurgie maxillo-faciale du CHU de rabat, l’atteinte des voies aériennes(VaS) l’atteinte médiastinale et le type de cellulite ont été retenu sur la tomodensitométrie. afin de dégager les éléments prédictifs de gravité statistiquement significatifs, l’évaluation a porté sur l’analyse des éléments épidémiologiques, cliniques, par acliniques et évolutifs en comparant respectivement les groupes de CCFD avec et sans atteinte des voies aériennes(VaS), avec et sans atteinte médiastinales, et en cas de formes nécrosantes versus cellulites phlegmoneuses. L’analyse statistique a été faite par le logiciel spss version 13.01 et les comparaisons ont été réalisées en utilisant les tests khi 2 et le test exact de Fisher pour les variables qualitatives, le test student et anOVa pour les variables quantitatives.Résultats : Cette série comporte 44 hommes et 34 femmes, L’âge moyen est 32 ans. Les facteurs favorisants significatifs sont, Le mauvais état buccodentaire et l’éthylotabagisme, alors que les aInS et Le diabète ne sont pas significatifs. Le diagnostic est clinique, et la tomodensitométrie permet l’étude de l’extension, le type, et de suivre l’évolution sous traitement. Les signes cliniques significatifs sont, l’altération de l’état général, le sepsis, la dyspnée, et les crépitations sous cutanées. Tous les malades ont été hospitalisés, dont 15 en réanimation, avec signification statistique pour le sepsis, l’atteinte médiastinale, et la cellulite nécrosante ou gangreneuse. Le drainage chirurgical (44,9%) avec signification pour médiastinites. L’évolution était favorable chez 75 patients ,3 décès par choc septiqueConclusion : Cette étude a montrée comme décrit dans la littérature que la CCFD prédomine chez le sujet jeune de sexe masculin, que la mauvaise hygiène bucco-dentaire intervient dans la genèse de la cellulite phlegmoneuse avec infiltration des VaS et que l’éthylotabagisme a un effet dans les formes graves cervico-médiastinales et nécrosantes .la clinique a permit le diagnostic mais elle a sous estimée l’atteinte des VaS et médiastinale et c’est la tomodensitométrie qui permit de préciser l’extension et le type de cellulite. L’antibiothérapie était comparable à la littérature, le drainage chirurgical des CCFD a été réalisé sous anesthésie générale avec intubation classique ou sous fibroscope, La trachéotomie n’est pas recommandée en première intention que lorsqu’elle était inévitable. Le recours à la chirurgie en urgence était pour les mêmes impératifs que la littérature dans les formes nécrotiques, dans l’atteinte médiastinale, et en cas de sepsis.Mots clés : Cellulite cervico-faciale - médiastinite –fasciite nécrosanteObjective : Cervicofacial cellulitis is a dermohypodermitis which originates at the hypodermic fat from a burglary of a focus dental, Its gravity lies partly in its diffuse form with a risk of airway obstruction and mediastinitis and secondly in its venture with necrotizing fasciitis and necrotizing gangrene. In the absence of multidisciplinary care and urgent, the evolution of these forms will be serious to sepsis, septic shock and multi-visceral dysfunction syndrome. The aim is to find predictors of extension from reaching the upper airways to mediastinal infiltration, as well as predictors of type of cellulitis (phlegmon or necrotic).Patients et méthods : retrospective study done over a period of 7 years who has exploited 78 cases of diffuse cervicofacial cellulitis (CCFD) collected in the service of Otolaryngology and maxillofacial Surgery University Hospital of rabat, achieving the airways (VaS), the mediastinal involvement and type of cellulite have been selected on the CT scan. To identify predictors of severity statistically significant, the evaluation focused on the analysis of the epidemiological, clinical, paraclinical and evolutionary elements by comparing respectively CCFD groups with and without airway involvement (VaS), with and without mediastinal involvement, and in case of necrotizing forms phlegmonous against cellulite. Statistical analysis was done by SPSS version 13.01 and comparisons were made using the chi 2 test and Fisher's exact test for qualitative variables, the Student test and anOVa for quantitative variables.Results: This series includes 44 men and 34 women; the average age is 32 years. Significant Contributing factors are the poor oral dental state, smoking and alcoholism . non-steroidal anti-inflammatory and diabetes were not significant. The diagnosis is clinical with discordance between the clinical and CT scan specifying the extension, type, and changes in treatment. The significant clinical signs are impairment of general condition, sepsis, dyspnea, and subcutaneous crepitus. all patients were hospitalized, including 15 in intensive care with statistical significance for sepsis, mediastinal involvement, and necrotizing or gangrene cellulitis. Surgical drainage (44.9%) with statistical significance for mediastinitis. The outcome was favorable in 75 patients, 3 deaths from septic shock.Conclusion: This study has shown as described in the literature that CCFD predominates in the young male, that poor oral hygiene is involved in the genesis of cellulite phlegmonous with airway infiltration and that smoking and alcoholism has effect in severe neck and mediastinal necrotizing. The clinical diagnosis allowed but she underestimated airway and mediastinal damage and computed tomography which enabled it to clarify the extent and type of cellulite. antibiotic therapy was comparable to the literature, surgical drainage of CCFD was performed under general anesthesia with classical intubation or under fiberscope, tracheostomy is not recommended as first-line until it was inevitable. The surgery was urgent for the same imperatives that literature in necrotic forms, in the mediastinal involvement, and sepsis.Keywords : cervico-facial cellulitis - mediastinitis - necrotizing fasciiti
On the absence of bound-state stabilization through short ultra-intense fields
We address the question of whether atomic bound states begin to stabilize in
the short ultra-intense field limit. We provide a general theory of ionization
probability and investigate its gauge invariance. For a wide range of
potentials we find an upper and lower bound by non-perturbative methods, which
clearly exclude the possibility that the ultra intense field might have a
stabilizing effect on the atom. For short pulses we find almost complete
ionization as the field strength increases.Comment: 34 pages Late
On the Influence of Pulse Shapes on Ionization Probability
We investigate analytical expressions for the upper and lower bounds for the
ionization probability through ultra-intense shortly pulsed laser radiation. We
take several different pulse shapes into account, including in particular those
with a smooth adiabatic turn-on and turn-off. For all situations for which our
bounds are applicable we do not find any evidence for bound-state
stabilization.Comment: 21 pages LateX, 10 figure
Ionization Probabilities through ultra-intense Fields in the extreme Limit
We continue our investigation concerning the question of whether atomic bound
states begin to stabilize in the ultra-intense field limit. The pulses
considered are essentially arbitrary, but we distinguish between three
situations. First the total classical momentum transfer is non-vanishing,
second not both the total classical momentum transfer and the total classical
displacement are vanishing together with the requirement that the potential has
a finite number of bound states and third both the total classical momentum
transfer and the total classical displacement are vanishing. For the first two
cases we rigorously prove, that the ionization probability tends to one when
the amplitude of the pulse tends to infinity and the pulse shape remains fixed.
In the third case the limit is strictly smaller than one. This case is also
related to the high frequency limit considered by Gavrila et al.Comment: 16 pages LateX, 2 figure
Multiphoton detachment of electrons from negative ions
A simple analytical solution for the problem of multiphoton detachment from
negative ions by a linearly polarized laser field is found. It is valid in the
wide range of intensities and frequencies of the field, from the perturbation
theory to the tunneling regime, and is applicable to the excess-photon as well
as near-threshold detachment. Practically, the formulae are valid when the
number of photons is greater than two. They produce the total detachment rates,
relative intensities of the excess-photon peaks, and photoelectron angular
distributions for the hydrogen and halogen negative ions, in agreement with
those obtained in other, more numerically involved calculations in both
perturbative and non-perturbative regimes. Our approach explains the extreme
sensitivity of the multiphoton detachment probability to the asymptotic
behaviour of the bound-state wave function. Rapid oscillations in the angular
dependence of the -photon detachment probability are shown to arise due to
interference of the two classical trajectories which lead to the same final
state after the electron emerges at the opposite sides of the atom when the
field is close to maximal.Comment: 27 pages, Latex, and PostScript figures fig1.ps, fig2.ps, fig3.ps,
accepted for publication in Phys. Rev.
Investigating the cross-talk between microglia and oligodendrocyte progenitors in brain ischemia
Oligodendrocytes, the myelin-forming cells in the brain, are severely affected by ischemia (Arai et al. 2009, Biol Pharm Bull), contributing to stroke-associated deficits. The possibility to implement spontaneous post-injury repair mechanisms still represents an unexplored field.
Recent data obtained by fate-mapping analysis using the conditional GPR17-iCreERT2xCAG-eGFP transgenic mice, showed that the subpopulation of adult Oligodendrocyte Progenitor Cells (OPCs) expressing the GPR17 receptor (GFP+-cells) represent \u201ca reserve pool\u201d that is maintained for repair purposes after brain damage (Vigano\u300 et al. 2016, Glia). Accordingly, our data demonstrated that, after brain ischemia, GFP+-cells actively respond to injury increasing their proliferation rate and migratory capacity. However, at later stages, only a few percentage of these cells undergo maturation. This limited post-stroke repair is likely due to local unfavourable inflammatory milieu mediated by macrophages and resident microglia, which participate to post-ischemic inflammation assuming both detrimental and beneficial phenotypes.
Here, we aimed at: (i) characterizing the spatio-temporal distribution of GFP+-cells in relation to microglia and macrophage polarization after brain ischemia in the middle cerebral artery occlusion MCAo, rodent model; (ii) exploring the cross-talk between microglia and OPCs, by assessing how vesicles released extracellularly (EVs) by microglia, polarized toward the pro- and anti- inflammatory states, influence OPC behaviour.
In vivo studies showed that GFP+-cells accumulate at the border of the ischemic lesion starting from 72h after ischemia, when immune cells show both pro- and anti-inflammatory features. One week after stroke, the absolute number of pro-inflammatory cells increases, whereas immune cells with anti-inflammatory phenotype were found to be decreased. In vitro studies pointed out that EVs produced by pro-inflammatory microglia limit OPC proliferation. On the contrary, 48h exposure to EVs from either pro- or anti-inflammatory microglia (but not resting cells) promote OPC maturation and myelination. Interestingly, EVs from pro-rigenerative cells also increased OPC migration. These data suggest that EVs contain signals able to influence OPC proliferation, migration and maturation. Shedding light on the mechanisms by which microglia activation interferes with the regeneration potential of OPCs is important for developing therapeutic interventions to implement functional recovery after stroke
- …