Éditeur(s) : HAL CCSD
Résumé : Report
The Canadian coastline is the longest of any country in the world, and is at risk from tsunamis generated in three oceans. The current state of knowledge precludes a complete probabilistic tsunami hazard assessment, which would require quantification of a wide range of possible scenarios for each tsunami source, coupled with modelling that incorporates fine-resolution bathymetry and onland topography to adequately assess potential runup at the coast. This preliminary assessment presents a first attempt to quantify the tsunami hazard on the Canadian Pacific, Atlantic and Arctic coastlines from local and far-field, earthquake and large landslide sources. For each source considered, we calculate the probability that tsunami runup at the coast will exceed 1.5 m (threshold for potential damage) and 3 m (significant damage potential), in a 50-year period. For each coastal region, we then combine the relative hazard from each source to calculate the overall probability that the coastline in question will experience tsunami runup exceeding 1.5 m (and 3 m) within a 50-year period, from any geological source. We also consider the maximum runup levels expected to occur within time periods of 100, 500, 1000, and 2500 years.
https://hal.archives-ouvertes.fr/hal-00856677

hal-00856677
https://hal.archives-ouvertes.fr/hal-00856677
DOI : 10.4095/292067

Éditeur(s) : HAL CCSD
Résumé : International audience
European journal of cancer (Oxford, England : 1990)

hal-01567818
https://hal.archives-ouvertes.fr/hal-01567818
PUBMED : 28527392

Résumé : L’objet de cette thèse est de présenter les spécificités épidémiologiques, étiologiques et thérapeutiques de la pathologie neurovasculaire dans la population noire spécifique que constitue la population martiniquaise. En 1998, l’étude ERMANCIA I a permis de mettre en évidence une surincidence des accidents vasculaires cérébraux (AVC) en Martinique d’environ 40% par rapport à la métropole avec une haute prévalence de l’hypertension artérielle et du diabète. Ces résultats ont participé à la création en 2003 de la 1ère unité neurovasculaire aux Antilles. Le suivi à 5 ans des patients ERMANCIA I a révélé que la moitié était décédée et que 50% des survivants présentaient une démence vasculaire (soit le double des cohortes métropolitaines), probablement favorisé par une microangiopathie cérébrale sous-jacente souvent sévère amplifiant l’impact cognitif de l’AVC. Ce suivi a également permis d’identifier les faiblesses de la prévention secondaire en Martinique avec près de 80% des hypertendus qui restent mal équilibrés justifiant la création en 2006 d’un réseau de prévention. L’efficacité de ce réseau a été évaluée montrant un taux élevé de bon contrôle tensionnel (74% vs 39%, p=0,01) et une morbi-mortalité vasculaire moindre à 2,5 ans (8,3% vs 24%, p<0,001) que chez les patients contrôles. En 2012, ERMANCIA II a permis de révéler une diminution majeure (en moyenne 30%) de l’incidence des AVC dans la population martiniquaise et de la mortalité à 1 mois pour les patients ≤55 ans (20% vs 8%, p=0,03) probablement en raison d’une meilleure implémentation des mesures de prévention primaire et de la prise en charge en UNV respectivement. Nos données ont également permis de décrire certaines spécificités étiologiques des AVC chez les Martiniquais : grande fréquence de l’athérome intracrânien (pour lequel nous apportons des arguments en faveur d’une nouvelle classification), infarctus choroïdiens antérieurs dont nous décrivons le profil évolutif particulier, infarctus lacunaires multiples sévères. Deux étiologies plus « classiques » comme la drépanocytose et les IC sur morsure de serpent sont devenues anecdotiques. En revanche, une dysplasie carotidienne focale, étiologie déjà décrite mais supposée rare , pourrait être responsable d’un tiers des infarctus carotidiens d’origine indéterminée chez les Afro-Caribéens ≤55 ans exposant à un risque élevé de récidive sous traitement antiagrégant (28% à 14 mois), contre aucun pour les patients traités par endartériectomie. Sur le plan thérapeutique, nos résultats sont en faveur d’un surrisque hémorragique de la thrombolyse standard chez les patients martiniquais les plus âgés, probablement en rapport avec un cumul de lésions microangiopathiques plus important. En l’absence de neuroradiologie interventionnelle en Martinique, nos travaux montrent que certains patients avec occlusion artérielle proximale résistante à la thrombolyse IV standard peuvent bénéficier d’un complément de thrombolytique (0,1mg/Kg de tenecteplase). Une étude randomisée est prévue afin de mieux mesurer le potentiel thérapeutique de cette stratégie. Pour conclure, l’intérêt de ces données est que la population martiniquaise partage très probablement beaucoup de ses « particularités » avec d’autres populations noires encore peu décrites et pour lesquelles l’occidentalisation progressive du mode de vie risque d’accentuer le fardeau représenté par les AVC.
Our work presented herein aimed to describe the epidemiological, etiological and therapeutic features of the stroke pathology in the Martinican Afro-Caribbean population. In 1998, the first population-based epidemiological study, ERMANCIA I, showed a 40% greater firstever stroke incidence in Martinique compared to those observed in continental France, with a high prevalence of hypertension and diabetes. These results contributed to the creation, in 2003, of the first stroke unit in the Caribbean area. In the 5_year follow-up study, we found that half of the patients had died and that 50% of survivors were affected from vascular dementia (twice compared with continental French cohorts): this figure was probably favored by severe underlying cerebral microangiopathy that amplified the cognitive impact of stroke. We also identified a failure in the secondary prevention in Martinique, certified by nearly 80% of hypertensive patients still insufficiently controlled. As a result, in 2006, we developed a well-structured stroke prevention network. The efficiency of this network was attested by the high rate of good blood pressure control (74% vs. 39%, p=0.01) and the reduced vascular morbidity and mortality rate (8.3% vs. 24%, p <0.001) after a 30-month period of activity, in comparison with control “historic” patients. In 2012, ERMANCIA II study revealed a 30% reduction of first-ever stroke incidence and a reduced mortality rate at 1 month for patients ≤55 years (8% vs. 20%, p = 0.03), compared to these observed in ERMANCIA I, likely due to improvement of primary stroke prevention and the best stroke unit management at the acute phase, respectively. Based on our etiological data, we underline: 1) the relatively high frequency of symptomatic intracranial atherosclerosis, for which we propose a new definition; 2) the clinic-radiological features of stroke in the anterior choroidal artery; 3) the atypical picture of “malignant” multilacunar syndrome. On the other hand, stroke due to sickle cell disease or “trigonocephale” snakebite were only anecdotal. However, we found that carotid-bulb atypical fibromuscular dysplasia (CAFD), a very unusual previously described cause of stroke, could be responsible for up to the third of carotidterritory stroke of so-called undetermined etiology among patients ≤55 years. In addition, the relatively high rate of recurrence under antiplatelet (28% at 14 months), was dramatically reduced by endarterectomy in patients with CAFD. From a therapeutic point of view, our results showed an excess rate of post-thrombolysis symptomatic intracerebral hemorrhages in older patients, a figure probably linked to the severe underlying hypertension-triggered cerebral microangiopathy. Owing to the lack of neurointerventionnal option in Martinique, we tested a new therapeutic strategy in patients with a proximal arterial occlusion not responsive to standard IV thrombolysis, consisting in an additional administration of IV tenecteplase, 0.1mg/kg. Our preliminary results were promising, leading us to plan a randomized study. Finally, most of the characteristics of stroke in this Afro-Caribbean population are probably shared by the majority of black people. Thus, our results could have a universal impact in the understanding of stroke burden in blacks.

http://www.theses.fr/2015AGUY0909/document

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
We review the evolution of concepts on and methods of estimating the state of stress from fault movements. Theories of failure in isotropic materials suggested a simple geometrical construction of optimal principal stress directions from a fault plane and its associated slip. These optimal directions align shear stress and slip directions and maximize the difference between shear stress and frictional resistance on the fault plane. Optimal stress directions for calcite twinning are obtained by a similar construction, with the difference that they maximize shear stress. Force representation of seismic sources independently introduced pressure, P, and tension, T, axes at positions that also maximize shear stress on both nodal planes. Frictional slip theory and the constraint that slip and shear stress directions be parallel allowed to address reactivation of pre-existing faults. This suggested that stress could also be inverted from reactivated fault and slip data or earthquake focal mechanisms. Early methods relied on geometrical constructions as a substitute for calculations, whereas later methods relied on software as these calculations became tractable with the help of computers. Similar methods were developed for the inversion of stress from crystal twin gliding with non-optimal geometry, with a different criterion that relies on a threshold of the component of shear stress along the gliding line. Even though these methods seek a common stress tensor compatible with fault and slip data, their main use is to separate polyphase data into homogeneous subsets and help deciphering complex tectonic histories. Fault and slip data can also be analyzed to constrain the strain rather than the stress tensor. In most cases this involves a summation and yields an average strain for the considered rock volume. Stress inversion thus appears better suited for differentiating heterogeneous data whereas strain analysis appears better suited for homogenizing them.
ISSN: 0040-1951

hal-00759043
https://hal.archives-ouvertes.fr/hal-00759043
DOI : 10.1016/j.tecto.2012.02.009

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Liposomal amphotericin B (LAmb) may fail to heal Leishmania infantum visceral leishmaniasis (VL) in the immunodeficient host. There are currently no guidelines on how to treat such patients and efficacy of miltefosine monotherapy seems limited in this indication. We present 2 cases of patients with VL and AIDS for which LAmb had to be interrupted (one because of toxicity, one because of treatment failure) and who were treated effectively with pentamidine followed by miltefosine.
ISSN: 1383-5769

hal-01509592
https://hal.archives-ouvertes.fr/hal-01509592
PUBMED : 27353022

Éditeur(s) : HAL CCSD IOS Press
Résumé : International audience
This study tested the hypothesis that trained sickle cell trait (SCT) carriers are not subjected to greater risk of rhabdomyolysis or renal failure in response to moderate submaximal exercise than subjects with normal hemoglobin (CONT). Blood markers in 11 trained SCT carriers and 12 control counterparts were measured before and after 40 min of exercise at 55% of peak power output (Ppeak) conducted in thermoneutral environment. Body weights decreased with exercise in the same proportion in the two groups (from 65.1 ± 7.0 kg to 64.1 ± 7.0 kg and from 70.2 ± 6.6 to 68.6 ± 6.6 kg at the end of exercise in SCT and CONT, respectively). Heart rate and rectal temperature increased in the two groups in response to exercise, but the groups remained closely matched. Serum urea, CRP, CK and LDH were similar in the two groups and remained unchanged in response to exercise. Creatinine, Na + , K + , Cl − and myoglobin concentrations increased above baseline in response to exercise, with changes of the same magnitude in the two groups. In summary, the results of the present study suggest that moderate submaximal exercise is not unsafe from a biochemical point of view for sportsmen carrying SCT.
ISSN: 1386-0291

hal-01163943
https://hal.univ-antilles.fr/hal-01163943
DOI : 10.3233/CH-2011-1524

Résumé : Dans le cas des DOM, singulièrement la Guadeloupe, qui sont à l'aube de l'expérimentation de réformes profondes de politiques économiques, l'élaboration d'un outil de simulation macroéconomique tel qu'un MEGC apparaît naturellement comme une exigence plus que souhaitable. Ce recours à la construction de modèles spécifiques pour les DOM est en parfaite cohérence avec l'une des principales conclusions du rapport d'information diligenté par le Sénat aux lendemains de la crise sociale du début de l'année 2009. Les appels à projet de la Commission europèenne et du Ministère de l'Outre-mer vont justement dans le sens de pallier celte carence puisque la politique économique des RUP de façon générale est conduite à vue sans aucun outil d'investigation ex ante. Nous avons conçu plusieurs modèles. Parmi eux, CloDyn est le premier modèle macroéconomique pour les DOM à vocationopérationnelle. Composée de plus de 2000 équations, ce modèle d'équilibre général calculable tient compte de nombreuses rigidités sur les marchés des biens et services et du travail et se décline sous deux versions: statique et dynamique. Les élasticités ont fait l'objet d'estimations économétriques. Il tient compte de nombreuses spécificités tant au niveau de la fiscalité de ces régions (octroi de mer, taxe sur les carburants, subventions à l'exportation) que du coût des facteurs (exonérations des charges sur les bas salaires, sur rémunératio des fonctionnaires). Il repose sur une formalisation des mécanismes en oeuvre dans ces économies que nous avons appelé le DOM disease pour expliquer les dysfonctionnements persistants sur le plan macroéconomique.
In the case of the French overseas regions, particularly of Guadeloupe, which are just beginning to experiment with economic policies radical reforrns, the development of a macroeconomic simulation tool such as a CGE model appears naturally as a highly desirable requirement. The use of the construction of specifie models for DOM is fully consistent with a major finding of the report commissioned by the Senate in the aftermath of the social crisis of the early 2009. As a malter of facts, the purpose of the calls for project initiated by the European Commission and the Ministry of Overseas is to remedy this deficiency, since the RUP economie policy is generally to conduct no investigation tool ex ante. We designed several models. Among them, CloDyn is the first operational DOM-based macroeconomic rnodel. Composed of more than 2000 equations, this computable general equilibrium model takes into account many rigidities in the markets for goods and services and labor and is available in two versions: static and dynamic. Elasticities have been econometrically estimated. lt rests on many features of both taxation (dock dues, fuel tax, export subsidies) and the cost factors (exemption from charges on low wages, remuneration of civil servants). Il is based on a formalization of the mechanisms at work in these economies we calied the DOM disease to explain the persistent failures in such economies. lt also evaluates the monetary poverty among households with the use of a block of microsimulation model and we allow a profane in GAMS to use this tool and conduct its own analytical work thanks to a user friendly interface.

http://www.theses.fr/2011AGUY0411/document

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The Taiwan area, where the Philippine Sea Plate collides with Eurasia, is one of the most seismically active areas in the world and has been consequently struck repeatedly by destructive earthquakes. To better constrain the occurrence of large earthquakes, we have conducted two cruises in 2012 and 2013 from which five piston, gravity and box-cores were retrieved from selected sites in targeted areas that contain continuous and accurate turbidite deposition offshore eastern Taiwan. Forty-seven turbidite layers deposited between 675 BC and 2012 AD have been described in the cores with facies varying from silty clay to coarse sand. We modeled each turbidite layer using the sedimentation rate deduced from radiocarbon age measurements performed on planktonic foraminifers. Precise dating based on 210Pb–137Cs chronology provided ages for the XXth century turbidites. Coring sites' locations, biotic association within turbidites beds and seismic calibration over the instrumental period, suggest that earthquakes are the most likely triggering mechanisms of turbidity currents over the last 2700 years. Calibration of correlations between turbidites and instrumental earthquakes allowed us to determine the minimum magnitude of recorded events (Mw = 6.8) and the maximum distance between the epicenter and the slope failure. Turbidites' synchroneity between cores has been tested but results showed that this criterion cannot be used in our study area because of the high level of seismicity, i.e., a M > 6.8 earthquake recurrence interval much smaller than the uncertainty on radiocarbon ages. The excellent accuracy of dating allows correlating all the turbidites deposited since 1920 with instrumental earthquakes. For each core, we established a return time ranging between 112 and 147 years for the period pre-1900 and ~ 27 and 34 years for the period post-1900. The discrepancy between pre-1900 and post-1900 recurrence either suggests, that slope stability varies, with higher slope instability after 1900 possibly due to increased sediment delivery by rivers.
ISSN: 0040-1951

hal-01467627
https://hal.archives-ouvertes.fr/hal-01467627
DOI : 10.1016/j.tecto.2016.04.030

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
BACKGROUND: Surveillance of HIV-1 drug resistance in treated patients with plasma viral load (VL) >50 copies/mL. METHODS: The protease and reverse transcriptase (RT) genes were systematically sequenced in samples from 756 patients with VL >50 copies/mL in 2009. The genotyping results were interpreted for each antiretroviral drug (ARV) by using the ANRS algorithm v21. Weighted analyses were used to derive representative estimates of percentages of patients. Prevalence rates were compared with those obtained in 2004 among patients with VL >1000 copies/mL. RESULTS: Sequences were obtained for 506 patients. Sequencing was successful in 45%, 80% and 96% of samples with VL of 51-500, 501-1000 and >1000 copies/mL, respectively. Resistance or possible resistance to at least one ARV was observed in 59% of samples. Overall, 0.9% of samples contained viruses resistant to all drugs belonging to at least three drug classes. All resistance prevalence rates were significantly lower in 2009 than in 2004. CONCLUSION: In France, where 86% of patients were receiving combination antiretroviral therapy in 2009, only 15.0% of patients had a VL >50 copies/mL, suggesting that only 8.9% of treated patients could potentially transmit resistant viruses. Only 0.08% of patients harboured viruses fully resistant to at least three antiretroviral drug classes. Further studies are needed to determine whether resistance continues to decline over time.
ISSN: 0305-7453

hal-00875092
https://hal.archives-ouvertes.fr/hal-00875092
DOI : 10.1093/jac/dkt033
PUBMED : 23404192