17 research outputs found
Numerical simulation and first-order hazard analysis of large co-seismic tsunamis generated in the Puerto Rico trench: near-field impact on the North shore of Puerto Rico and far-field impact on the US East Coast
We perform numerical simulations of the coastal impact of large co-seismic tsunamis, initiated in the Puerto Rican trench, both in far-field areas along the upper US East coast (and other Caribbean islands), and in more detail in the near-field, along the Puerto Rico North Shore (PRNS). We first model a magnitude 9.1 extreme co-seismic source and then a smaller 8.7 magnitude source, which approximately correspond to 600 and 200 year return periods, respectively. In both cases, tsunami generation and propagation (both near- and far-field) are first performed in a coarse 2′ basin scale grid, with ETOPO2 bathymetry, using a fully nonlinear and dispersive long wave tsunami model (FUNWAVE). Coastal runup and inundation are then simulated for two selected areas, using finer coastal nested grids. Thus, a 15″ (450 m) grid is used to calculate detailed far-field impact along the US East Coast, from New Jersey to Maine, and a 3″ (90 m) grid (for the finest resolution), encompassing the entire PRNS, is used to compute detailed near-field impact along the PRNS (runup and inundation). To perform coastal simulations in nested grids, accurate bathymetry/topography databases are constructed by combining ETOPO2 2′ data (in deep water) and USGS\u27 or NOAA\u27s 15″ or 3″ (in shallow water) data. In the far-field, runup caused by the extreme 9.1 source would be severe (over 10 m) for some nearby Caribbean islands, but would only reach up to 3 m along the selected section of the East coast. A sensitivity analysis to the bathymetric resolution (for a constant 3″ model grid) of runup along the PRNS, confirms the convergence of runup results for a topographic resolution 24″ or better, and thus stresses the importance of using sufficiently resolved bathymetric data, in order to accurately predict extreme runup values, particularly when bathymetric focusing is significant. Runup (10–22 m) and inundation are found to be very large at most locations for the extreme 9.1 source. Both simulated spatial inundation snapshots and time series indicate, the inundation would be particularly severe near and around the low-lying city of San Juan. For the 8.7 source, runup along the PRNS would be much less severe (3–6 m), but still significant, while inundation would only be significant near and around San Juan. This first-order tsunami hazard analysis stresses the importance of conducting more detailed and comprehensive studies, particularly of tsunami hazard along the PRNS, for a more complete and realistic selection of sources; such work is ongoing as part of a US funded (NTHMP) tsunami inundation mapping effort in Puerto Rico
Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients
Seasonal variability of living benthic foraminifera from the West-Gironde mud patch (Bay of Biscay, NE Atlantic): Three contrasted periods under the stereomicroscope
International audienceLiving continental shelf foraminifera were studied at three stations along a shore to open ocean transect between 39 and 69 m depth in the West-Gironde Mud Patch (WGMP) (Bay of Biscay, NE Atlantic). The aim of this work was to understand how the complex temporal variability of the environmental conditions (e.g., hydrosedimentary processes, sedimentary organic matter, oxygenation levels) controls foraminiferal ecological patterns (i.e., diversity, faunal composition, standing stock, and microhabitats). The WGMP was sampled during three different seasons (boreal summer – August 2017; winter – February 2018 and spring – April 2018), with very different meteorological patterns and benthic environmental conditions. The sedimentary facies at the shallowest station (Station 1, 39 m) varies significantly due to hydrometeorological constraints (strong storms and swells), which are extremely marked in late autumn and during the winter. The erosion of the sandy substrate by strong bottom currents and the deposition of a silty surface layer leads to the recorded spectacular drop in foraminiferal diversity and density recorded in February and April 2018. All foraminiferal species were affected by this hydrosedimentary instability, likely due to the partial destruction of their microhabitat by intense erosional and depositional processes. At the middle WGMP station (Station 2, 47 m), benthic fauna changed much more gradually. The sedimentary imprint of the spring phytoplankton bloom is clearly recorded in April 2018 with an increase in fresh and altered phytopigment content in surface sediments. Eggerelloides scaber, a deposit feeder and hypoxia-tolerant species, dominated the 2017 summer foraminiferal fauna but was gradually replaced by Ammonia falsobeccarii, a phytophagous taxon considered quite reactive to spring bloom inputs. At the distal WGMP (Station 4, 69 m), E. scaber and A. falsobeccarii were outcompeted and gradually replaced by Nonion faba and Nonionoides turgidus, both highly adaptable species able to settle down in surface and subsurface sediments during the spring bloom periods. Able to endure a range of microhabitats and food availability, there they rely on both fresh and altered phytodetritus. We propose a conceptual scheme summarizing the putative interconnexion between foraminiferal faunas, geochemistry and physics in the WGMP
Live (stained) benthic foraminifera from the West-Gironde Mud Patch (Bay of Biscay, NE Atlantic): Assessing the reliability of bio-indicators in a complex shelf sedimentary unit.
Live (stained) benthic foraminifera from the West-Gironde Mud Patch (Bay of Biscay, NE Atlantic): Assessing the reliability of bio-indicators in a complex shelf sedimentary unit.
Live (Rose Bengal stained) shelf foraminiferal faunas have been studied at seven stations located along a shore-open ocean transect between 39 and 69-m depth in the West-Gironde Mud Patch (WGMP) (Bay of Biscay, NE Atlantic) to understand how complex environmental conditions (e.g., organic matter, oxygenation, sedimentary facies) control their ecological patterns (i.e., diversity, faunal composition, standing stock, and microhabitats). To do so, the WGMP was sampled in August 2017, at the end of the succession of phytoplankton blooms occurring in spring and summer. This morpho-sedimentary unit is bathed by well-oxygenated bottom waters and characterized by clay-silt facies containing variably degraded phytodetritus and traces of terrestrial organic matter. Oxygen penetration depth within the sediment is less than 7 ± 3 mm, indicating efficient organic matter in-sediment mineralization by aerobic respiration. Foraminiferal richness (S) presents relatively moderate values ranging between 15 and 35 taxa. According to Shannon Index H’, foraminiferal diversity tends to increase with water depth. Accordingly, the relative contribution of Eggerelloides scaber, the dominant foraminiferal species at all stations, decreases with increased depth and decreased proximity to the coast. The shallowest station (Station 1, 39 m), closest to the shore, is characterised by E. scaber, Quinqueloculina laevigata and Ammonia beccarii, species typical of inner-shelf environments constrained by high-energy hydrodynamics and river discharge. Surficial sediments at Station 1 constitute of winnowed sands depleted in organic carbon. Towards the centre of the WGMP, where clay-silt facies contain variably degraded marine phytodetritus and terrestrial organic compounds, foraminiferal faunas are characterized by Bulimina aculeata, Ammonia falsobeccarrii, Nouria polymorphinoides and Nonionoides turgidus. Yet E. scaber remains the most dominant taxon. Deeper stations (>55 m depth) located at the distal part of the mud patch are dominated by B. aculeata, A. falsobeccarrii, N. polymorphinoides and E. scaber. Accompanying these taxa are Bulimina marginata, Rectuvigerina phlegeri, Nonion faba and Paracassidulina neocarinata, which are typical of mid- and outer-shelf ecosystems enriched in sedimentary organic matter
Données comparatives moléculaires, précliniques et cliniques des différentes souches de bacille de Calmette-Guérin (BCG) : revue de la littérature du Comité de cancérologie de l’Association française d’urologie (CCAFU)
International audienceOBJECTIVE:To review the differences between the BCG strains used for the treatment of non-muscle invasive bladder cancer (NMIBC) at the molecular level, regarding cytotoxicity, immunogenicity, clinical efficiency, and safety.MATERIAL AND METHOD:A systematic review of the literature search was performed from the database MedLine, focused on the following keywords: BCG; bladder; strain; genome; cytotoxicity; immune response; efficiency; safety.RESULTS:Genetic differences between BCG strains have been identified and correlated to their time to differentiation from their initial cultures start, assuming a lower resistance to the host immune defenses of Tice and Danish strains compared to the Connaught strain. Preclinical comparative data showed superior cytotoxic effect and immunogenicity of the Connaught strain compared to Tice and Danish strains. The phase III trials have shown superior efficiency of BCG Connaught compared to BCG Tice and BCG Danish compared to BCG Tice regarding recurrence-free survival.CONCLUSIONS:Among BCG strains used in France in NMIBC treatment, preclinical and clinical efficiency of Connaught strain was higher than that of the Tice strain. The limits of the currently available studies lie primarily in the lack of use of maintenance therapy
[CCAFU french national guidelines 2016-2018 on bladder cancer].
International audienceOBJECTIVE:The purpose of the guidelines national committee CCAFU on bladder cancer was to propose updated french guidelines for non-muscle invasive (NMIBC) and invasive (MIBC) bladder cancers.METHODS:A Medline search was achieved between 2013 and 2016, as regards diagnosis, options of treatment and follow-up of bladder cancer, to evaluate different references with levels of evidence.RESULTS:Diagnosis of NMIBC (Ta, T1, CIS) is based on a complete deep resection of the tumour. The use of fluorescence and a second-look indication are essential to improve initial diagnosis. Risks of both recurrence and progression can be estimated using the EORTC score. A stratification of patients into low, intermediate and high risk groups is pivotal for recommending adjuvant treatment : instillation of chemotherapy (immediate post-operative, standard schedule) or intravesical BCG (standard schedule and maintenance). Cystectomy is recommended in BCG-refractory patients. Extension evaluation of MIBC is based on pelvic-abdominal and thoracic CT-scan; MRI and FDG-PET remain optional. Cystectomy associated with extensive pelvic lymph nodes resection is considered the gold standard for non metastatic MIBC. An orthotopic bladder substitution should be proposed to both male and female patients lacking any contraindications and in cases of negative frozen urethral samples. The interest of neoadjuvant chemotherapy is well known for all MIBC, wathever the stage. Thus, neoadjuvant chemotherapy is recommended for all eligible patients according PS (PS 60ml/mn). As regards metastatic MIBC, first-line chemotherapy using platin is recommended (GC or MVAC). In second line treatment, only chemotherapy using vinflunine has been validated to date, even if results of immunotherapy clinical trials are encouraging.CONCLUSION:These updated french guidelines will contribute to increase the level of urological care for the diagnosis and treatment for NMIBC and MIBC. © 2016 Elsevier Masson SAS. All rights reserved
Enquête observationnelle du Comité de cancérologie de l’association française d’urologie (CCAFU) sur la pratique des instillations postopératoires précoces (IPOP) de mitomycine C pour le traitement des tumeurs de vessie n’infiltrant pas le muscle (TVNIM)
International audienceOBJECTIVE:To evaluate the practice of immediate postoperative instillation (IPOP) using mitomycin C for non-muscle invasive bladder cancer (NMIBC) treatment by urologists members of the French Association of Urology (AFU).MATERIAL AND METHOD:Internet-based observational survey evaluating indications and practical modalities of IPOP in NMIBC treatment using questionnaire sent in May 2014 to 915 urologists.RESULTS:Two hundred ninety-eight urologists participated in the survey (response rate: 32.6%) and 57% prescribed the IPOP. The median frequency of IPOP prescription was 3.3%, and was higher in the academic public sector. The CASE recommendations were self-assessed as known or well-known in 67% of cases. The selections criteria for IPOP were adequately identified by 62% of urologists, without differences according to sectors of activity. The IPOP prescription modalities were declared as an obstacle to the completion for 41.9% of urologists, and especially in the private sector. Completion times of IPOP were declared <24h in 91% of cases. We see that 28.5% of urologists prescribed an urinary alkalization. The average frequency of complications of IPOP was 0.91 per urologist.CONCLUSIONS:The IPOP prescription frequency was higher among urologists practicing in the academic sector. Neither the level of knowledge of the recommendations nor the frequency of complications of IPOP had explained this difference. However, the prescription modalities were more frequently reported as an obstacle to their completion in the private sector.LEVEL OF EVIDENCE:3