Faint dwarf galaxies in the Next Generation Virgo cluster Survey

The Next Generation Virgo Cluster Survey (NGVS) is a CFHT Large Program that is using the wide field of view capabilities of the MegaCam camera to map the entire Virgo Cluster from its core to virial radius. The observing strategy has been optimized to detect very low surface brightness structures in the cluster, including intracluster stellar streams and faint dwarf spheroidal galaxies. We present here the current status of this ongoing survey, with an emphasis on the detection and analysis of the very low-mass galaxies in the cluster that have been revealed by the NGVS.Comment: 6 pages, 2 figures, Conference Proceedings: "A Universe of Dwarf Galaxies", 14-18 June 2010, Lyon, Franc

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Mapping and analysis of maritime claims in the Russian Arctic based on POLARIS System

International audienceDuring the last decade, more than 500 maritime claims have been reported in the Arctic and the political will of the Russian government to develop the Northern Sea Route (NSR) for the exportation of raw materials may lead to a rise of events. However, data on maritime claims in the Russian Arctic are rather missing and not updated which hinders accurate analysis so far. Through an evaluation of maritime claims occurred in the Russian Arctic during the period 2007-2018, this article aims to identify their primary root causes in order to determine if the new Polar Code risk mitigation measures and POLARIS system especially, would have prevented their occurrence. Based on empirical data collection, the study gathers, classifies and maps claims occurred along the NSR till the Polar Code enforcement. The POLARIS System is used for specific case study to determine if it occurred in areas where ice conditions represented a direct risk for the integrity of the vessel. As results, the manuscript provides a categorization of maritime claims in the Russian Arctic in accordance with IMO standards and sheds a light on the type of risk occurrence a ship may face along the NSR. It brings valuable implications for maritime operators who are still expecting historical data for proper risk assessment in the Russian Arctic. Finally, it demonstrates that POLARIS is an appropriate tool for risk mitigation and how stakeholders can implement and share in their common interest best practices and data

What can we learn from 9 years of ticketing data at a major transport hub? A structural time series decomposition

Mobility demand analysis is increasingly based on smart card data, that are generally aggregated into time series describing the volume of riders along time. These series present patterns resulting from multiple external factors. This paper investigates the problem of decomposing daily ridership data collected at a multimodal transportation hub. The analysis is based on structural time series models that decompose the series into unobserved components. The aim of the decomposition is to highlight the impact of long-term factors, such as trend or seasonality, and exogenous factors such as maintenance work or unanticipated events such as strikes or the COVID-19 health crisis. We focus our analysis on incoming flows of passengers to two transport lines known to be complementary in the Parisian public transport network. The available ridership data allows analysis over both long-term and short-term time horizons including significant events that have impacted people&apos;s mobility in the Paris region

Renal cell carcinoma (RCC) in patients with end-stage renal disease exhibits many favourable clinical, pathologic, and outcome features compared with RCC in the general population.

International audienceBACKGROUND: Patients with end-stage renal disease (ESRD) are at risk of developing renal tumours. OBJECTIVE: Compare clinical, pathologic, and outcome features of renal cell carcinomas (RCCs) in ESRD patients and in patients from the general population. DESIGN, SETTING, AND PARTICIPANTS: Twenty-four French university departments of urology participated in this retrospective study. INTERVENTION: All patients were treated according to current European Association of Urology guidelines. MEASUREMENTS: Age, sex, symptoms, tumour staging and grading, histologic subtype, and outcome were recorded in a unique database. Categoric and continuous variables were compared by using chi-square and student statistical analyses. Cancer-specific survival (CSS) was assessed by Kaplan-Meier and Cox methods. RESULTS AND LIMITATIONS: The study included 1250 RCC patients: 303 with ESRD and 947 from the general population. In the ESRD patients, age at diagnosis was younger (55 ± 12 yr vs 62 ± 12 yr); mean tumour size was smaller (3.7 ± 2.6 cm vs 7.3 ± 3.8 cm); asymptomatic (87% vs 44%), low-grade (68% vs 42%), and papillary tumours were more frequent (37% vs 7%); and poor performance status (PS; 24% vs 37%) and advanced T categories (≥ 3) were more rare (10% vs 42%). Consistently, nodal invasion (3% vs 12%) and distant metastases (2% vs 15%) occurred less frequently in ESRD patients. After a median follow-up of 33 mo (range: 1-299 mo), 13 ESRD patients (4.3%), and 261 general population patients (27.6%) had died from cancer. In univariate analysis, histologic subtype, symptoms at diagnosis, poor PS, advanced TNM stage, high Fuhrman grade, large tumour size, and non-ESRD diagnosis context were adverse predictors for survival. However, only PS, TNM stage, and Fuhrman grade remained independent CSS predictors in multivariate analysis. The limitation of this study is related to the retrospective design. CONCLUSIONS: RCC arising in native kidneys of ESRD patients seems to exhibit many favourable clinical, pathologic, and outcome features compared with those diagnosed in patients from the general population