1,090 research outputs found
Analyse du cycle de vie de nouveaux mortiers contenant des argiles calcinées comme additions : le projet CO2REDRES
peer reviewedDepuis longtemps, le ciment Portland a prouvé son utilité dans les constructions conventionnelles en béton. Cependant, malgré ses nombreuses qualités, ce matériau est également responsable d’importantes émissions de gaz à effet de serre et d'une consommation significative d’énergie. Ces inconvénients sont liés à la production du clinker, constituant majeur du ciment. Pendant longtemps, le laitier de haut fourneau et les cendres volantes ont été utilisés comme substituants partiels du clinker afin d'en diminuer l'utilisation, et réduire ainsi les impacts environnementaux du ciment. Ces matériaux secondaires se raréfient dans plusieurs zones géographiques, y compris dans la Grande Région. C’est dans ce contexte que le projet CO2REDRES prend place, ayant pour but de démontrer la faisabilité de la production d’additions minérales ayant des propriétés hydrauliques et/ou pouzzolaniques à partir de ressources secondaires (déchets ou sous-produits industriels). La présente étude expose l’analyse du cycle de vie de cette nouvelle production d’additions minérales, afin d'en caractériser les impacts environnementaux et de démontrer leurs avantages potentiels en substitution.CO2REDRES11. Sustainable cities and communities13. Climate action9. Industry, innovation and infrastructur
Utilisation du test GeneXpert pour le diagnostic de la tuberculose au service des maladies infectieuses du CHNU de Fann
Introduction: Nous avons réalisé ce travail pour montrer notre expérience d’utilisation du GeneXpert et évaluer son apport dans la confirmation du diagnostic de la tuberculose. Méthodes: Etude prospective descriptive et analytique de janvier à Décembre 2013. Résultats: Quatre vingt quatorze patients ont bénéficié du geneXpert pour le dépistage de la tuberculose toute localisation confondue. Le geneXpert avait été positif dans 62% des cas. Les images radiologiques fortement évocatrices de tuberculose était associées à un geneXpert positif dans 25% des cas. La recherche de BAAR réalisée chez 55 patients était positive dans 9 cas (16%). Le geneXpert était positif sur 46 frottis négatif (54%)et dans 89% sur les frottis positifs. La prévalence de la tuberculose extrapulmonaire était de 34%. Le taux de positivité était variable en fonction du type de prélèvement. Deux cas de résistance à la rifampicine ont été détectées. Conclusion: Le geneXpert a été d’un grand apport pour le diagnostic de la tuberculose pulmonaire et extrapulmonaire mais la bacilloscopie reste incontournable.Pan African Medical Journal 2016; 2
Hepatitis B screening practices and viral control among persons living with HIV in urban Senegal.
Chronic hepatitis B virus (HBV) infection affects >10% of the general population and is the leading cause of liver cirrhosis and cancer in West Africa. Despite current recommendations, HBV is often not tested for in clinical routine in the region. We included all people living with HIV (PLWH) in care between March and July 2019 at Fann University Hospital in Dakar (Senegal) and proposed hepatitis B surface antigen (HBsAg) test to those never tested. All HBsAg-positive underwent HIV and HBV viral load (VL) and liver stiffness measurement. We evaluated, using logistic regression, potential associations between patient characteristics and (a) HBV testing uptake; (b) HIV/HBV co-infection among individual HBsAg tested. We determined the proportion of co-infected who had HBV DNA >20Â IU/ml on ART and sequenced HBV polymerase in those with HBV replication.of 1076 PLWH in care, 689 (64.0%) had never had an HBsAg test prior to our HBV testing intervention. Women and individuals >40Â years old were less likely to have been previously tested. After HBV testing intervention,107/884 (12.1%) PLWH were HBsAg-positive. Seven of 58 (12.1%) individuals newly diagnosed with HIV/HBV co-infection had a detectable HBV VL, of whom five were HIV-suppressed. Two patients on ART including 3TC and AZT as backbone showed the presence of the triple resistance mutation 180M/204I/80V. In this Senegalese urban HIV clinic, the majority of patients on ART had never been tested for HBV infection. One in ten co-infected individuals had a detectable HBV VL despite HIV suppression, and 8% were not receiving a TDF-containing regimen
Prevalence and Predictors of Liver Fibrosis in People Living with Hepatitis B in Senegal.
Hepatitis B virus (HBV) infection is the first cause of liver cirrhosis and cancer in West Africa. Although the exposure to additional environmental and infectious risk factors may lead to the faster progression of liver disease, few large-scale studies have evaluated the determinants of HBV-related liver fibrosis in the region. We used transient elastography to evaluate the prevalence of liver fibrosis and assessed the association between HBV markers and significant liver fibrosis in a cohort of people living with HBV in Dakar, Senegal. The prevalence of significant liver fibrosis was 12.5% (95% confidence interval [CI] 9.6%-15.9%) among 471 people with HBV mono-infection (pwHBV) and 6.4% (95% CI 2.6%-12.7%) in 110 people with HIV/HBV co-infection (pwHIV/HBV) on tenofovir-containing antiretroviral therapy (p = 0.07). An HBV viral load > 2000 IU/mL was found in 133 (28.3%) pwHBV and 5 (4.7%) pwHIV/HBV, and was associated with significant liver fibrosis (adjusted odds ratio (aOR) 1.95, 95% CI 1.04-3.66). Male participants (aOR 4.32, 95% CI 2.01-8.96) and those with elevated ALT (aOR 4.32, 95% CI 2.01-8.96) were especially at risk of having significant liver fibrosis. Our study shows that people with an HBV viral load above 2000 IU/mL have a two-fold increase in the risk of liver fibrosis and may have to be considered for antiviral therapy, independent of other disease parameters
AdS Black Hole Solutions in the Extended New Massive Gravity
We have obtained (warped) AdS black hole solutions in the three dimensional
extended new massive gravity. We investigate some properties of black holes and
obtain central charges of the two dimensional dual CFT. To obtain the central
charges, we use the relation between entropy and temperature according to the
AdS/CFT dictionary. For AdS black holes, one can also use the central charge
function formalism which leads to the same results.Comment: 24pages, some organization corrected, minor corrections, references
added, final published versio
Warped black holes in 3D general massive gravity
We study regular spacelike warped black holes in the three dimensional
general massive gravity model, which contains both the gravitational
Chern-Simons term and the linear combination of curvature squared terms
characterizing the new massive gravity besides the Einstein-Hilbert term. The
parameters of the metric are found by solving a quartic equation constrained by
an inequality that imposes the absence of closed timelike curves. Explicit
expressions for the central charges are suggested by exploiting the fact that
these black holes are discrete quotients of spacelike warped AdS(3) and a known
formula for the entropy. Previous results obtained separately in topological
massive gravity and in new massive gravity are recovered as special cases.Comment: 38 pages, 7 figures. v2: minor changes, added refs and an appendix on
self-dual and null z-warped black hole
Holographic Renormalization and Stress Tensors in New Massive Gravity
We obtain holographically renormalized boundary stress tensors with the
emphasis on a special point in the parameter space of three dimensional new
massive gravity, using the so-called Fefferman-Graham coordinates with relevant
counter terms. Through the linearized equations of motion with a standard
prescription, we also obtain correlators among these stress tensors. We argue
that the self-consistency of holographic renormalization determines counter
terms up to unphysical ambiguities. Using these renormalized stress tensors in
Fefferman-Graham coordinates, we obtain the central charges of dual CFT, and
mass and angular momentum of some black hole solutions. These results are
consistent with the previous ones obtained by other methods. In this study on
the Fefferman-Graham expansion of new massive gravity, some aspects of higher
curvature gravity are revealed.Comment: Version accepted for publication in JHEP, conclusion revised,
references adde
On asymptotically AdS-like solutions of three dimensional massive gravity
In this paper we have added Maxwell, Maxwell-Chern-Simons and gravitational
Chern-Simons terms to Born-Infeld extended new massive gravity and we have
found different types of (non)extremal charged black holes. For each black hole
we find mass, angular momentum, entropy and temperature. Since our solutions
are asymptotically AdS or warped-AdS, we infer central charges of dual CFTs by
using Cardy's formula. Computing conserved charges associated to asymptotic
symmetry transformations confirms calculation of central charges. For CFTs dual
to asymptotically AdS solutions we find left central charges from Cardy's
formula, while conserved charge approach gives both left and right central
charges. For CFTs dual to asymptotically warped-AdS solutions, left and right
central charges are equal when we have Maxwell-Chern-Simons term but they have
different values when gravitational Chern-Simons term is included.Comment: 30 pages, 11 tables. Improved version (two new sections added for
asymptotic conserved charges). Accepted in JHE
Tuberculose intestinale révélée par une occlusion intestinale aigüe au cours d’une réaction paradoxale au traitement anti-tuberculeux chez un patient immunocompétent: à propos d’un cas et revue de la littérature
La tuberculose intestinale représente 3 à 5% de toutes les localisations viscérales. Malgré l'efficacité démontrée des anti-tuberculeux, des cas d'exacerbation du tableau clinique initial ont été décrits à l'initiation du traitement. Ces réactions dites «paradoxales» sont cependant rarement rapportées chez les immunocompétents et beaucoup moins sous forme d'occlusion intestinale. Nous rapportons un cas de tuberculose intestinale révélée par une occlusion intestinale aigüe au cours d'une réaction paradoxale aux anti-tuberculeux. Il s'agit d'un patient de 26 ans, immunocompétent qui a présenté un syndrome occlusif à un mois de traitement d'une tuberculose pleuro-pulmonaire. La tomodensitométrie (TDM) abdominale était en faveur d'une occlusion intestinale grêlique. La laparotomie objectivait une masse intra-péritonéale avec de multiples adhérences. L'examen anatomopathologique de la pièce opératoire était en faveur d'une tuberculose intestinale. L'évolution était favorable après la poursuite du traitement anti-tuberculeux initial
Staphylococcal Panton-Valentine Leucocidin as a Major Virulence Factor Associated to Furuncles
Panton-Valentine Leucocidin (PVL), one of the β-barrel pore-forming staphylococcal leucotoxins, is known to be associated to furuncles and some severe community pneumonia. However, it is still uncertain how many other virulence factors are also associated to furuncles and what the risk factors of furuncles are in immuno-compromised status of patients, especially the HIV (+) patients. In this paper, we use antigen immunoprecipitation and multiplex PCR approach to determine the presence of 19 toxins, 8 adhesion factors and the PFGE profiles associated to furuncles in three independent patient study groups of S. aureus (SA) isolates collected from the Cayenne General Hospital (French Guiana). The patient groups were made of: 16 isolates from HIV (−) patients, 9 from HIV (+) patients suffering from furuncles, and 30 control isolates from patients with diverse secondary infected dermatitis. Our data reveals that the majority (96%) of SA strains isolated from HIV patient-derived furuncles significantly produced PVL (p<10−7), whereas only 10% of SA strains produced this toxin in secondary infected dermatosis. A high prevalence of LukE-LukD-producing isolates (56 to 78%) was recorded in patient groups. Genes encoding clumping factor B, collagen- and laminin-binding proteins (clfB, cna, lbp, respectively) were markedly frequent (30 to 55%), without being associated to a specific group. Pulse field gel electrophoresis evidenced 24 overall pulsotypes, whereas the 25 PVL-producing isolates were distributed into 15 non clonal fingerprints. These pulsotypes were not specific PVL-producing isolates. PVL appears to be the major virulence factor associated to furuncles in Europe and in South America regardless of the immune status of the HIV patients
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