Devenir du CODB dans les réseaux de distribution Etude de 2 cas

Cet article rapporte les résultats de campagnes de mesure de Carbone Organique Dissous Biodégradable sur 2 sites en exploitation. Les mesures de CODB ont été effectuées par la méthode rom et tom. La première partie de l'étude concerne le site de KERNE UHEL. Il s'agit d'une usine de traitement d'eau de surface comprenant une étape d'ozonation suivie d'une filtration sur CAG récemment mise en place. L'ozonation provoque une augmentation de CODB de 0,3 à 0,6 mg O. Le CAG élimine le CODB : on a 100 % d'élimination lorsqu'il est neuf, et jusqu'à 80 % d'élimination sur un pilote après 1 an de fonctionnement. Dans le réseau, an observe une diminution du CODB lorsque la concentration de celui-ci est de 0,6 - 0,7 mg 1-1 dans l'eau traitée, cela malgré la présence de chlore libre. Lorsque le CODB de l'eau traitée est de 0,14 mgl-1 (après mise en route de la filière CAG) l'évolution dans le réseau est beaucoup plus difficile à mesurer (0,14 < CODB < 0,27 mg l-1). Le deuxième site étudié est le réseau de VIENNE-BRIANCE. 4 campagnes de mesures effectuées entre Juin et Août 1991 sur 10 points de prélèvement, montrent qu'il y a consommation de CODB, surtout en période chaude et aux extrémités du réseau. On a également des relargages de CODB, un nombre significatif de valeurs se trouvant au-dessus de la valeur maximale observée à l'usine. On remarque une grande variabilité des valeurs sur le réseau (< 0,1 à 0,6 mg l-1) en comparaison avec la gamme de valeurs obtenues sur l'eau traitée (0,21- 0,30 mg l-1).This study reports results of BDOC measurements from two experimental sites. BDOC was measured by JORET and LEVI’S method, in which a sample is incubated at 20 °C with colonised sand. Dissolved Organic Carbon is evaluated every day, and BDOC calculated as Initial DOC minus the minimal DOC observed during incubation. Reliability of this method was verified by measuring BDOC of standard acetate solutions. We obtained coefficients warrying between 2 and 5 % for BDOC about 1,0 mg l-1.The first part of the study concerns KERNE UHEL treatment plant and its distribution network. BDOC was measured on sand filtered water, ozonated water, GAC filtered water, treated water and on five reservoirs along the network. Results from the treatment plant show that ozonation generates BDOC (increase of 0.3 to 0.6 mg l-1) GAC filtration allows very low levels of BDOC to be obtained when filtration start up (< 0.1 mg l-1) On GAC pilot plant, BDOC removed was between 50 % and 80 % after one year. In distribution, BDOC concentration 'decreased tram 0,6 - 0,7 mg l-1 to 0,2 - 0,4 mgl-1, during an estimated residence lime of 190 h. When the entire GAC filters were commissioned on the treatment plant, treated water BDOC was equal to 0.14 mg l-1; and between 0.14 and 0.27 mg l-1 in the network. This shows that BDOC reduction in the treatment plant reduces its evolution in the distribution system.The second part of the study was conducted on the distribution network of VIENNE BRIANCE, which is supplied with water from the river VIENNE. This water is treated by coagulation, settlement and sand filtration. This network is very extensive and provides water to more than 20 rural villages. Ten points were selected on the network, and were monitored for BDOC, chemical and bacteriological parameters from June to August 1991. Results of physico chemical analyses showed variation of temperature (-3 °C to + 3 °C in the network compared to the treated water at the station); pH (slight variations < 0,5 pH units) and turbidity (increase in the network with peak values as high as 3,5 NTU). Treatment plant's BDOC values were between 0.2 - 0.4 mg l-1. In the network, a great variation is observed : < 0.1 to 0.6 mg l-1. This shows that microbiological activity in the system causes BDOC consumption, but also BDOC is released kilo the water. Heterotrophic bacteria coutils increases during distribution and filamentous fungi have also been isolated in this network.The results of this study pointed out the difficulty to interprete BROC evolution in the network, especially when the hydraulic of the system is not well understood

Transformation-adversarial network for road detection in LIDAR rings, and model-free evidential road grid mapping.

International audienceWe propose a deep learning approach to perform road-detection in LIDAR scans, at the point level. Instead of processing a full LIDAR point-cloud, LIDAR rings can be processed individually. To account for the geometrical diversity among LIDAR rings, an homothety rescaling factor can be predicted during the classification, to realign all the LIDAR rings and facilitate the training. This scale factor is learnt in a semi-supervised fashion. A performant classification can then be achieved with a relatively simple system. Furthermore, evidential mass values can be generated for each point from an observation of the conflict at the output of the network, which enables the classification results to be fused in evidential grids. Experiments are done on real-life LIDAR scans that were labelled from a lane-level centimetric map, to evaluate the classification performances

Evidential deep learning for arbitrary LIDAR object classification in the context of autonomous driving

International audienceIn traditional LIDAR processing pipelines, a point-cloud is split into clusters, or objects, which are classified afterwards. This supposes that all the objects obtained by clustering belong to one of the classes that the classifier can recognize, which is hard to guarantee in practice. We thus propose an evidential end-to-end deep neural network to classify LIDAR objects. The system is capable of classifying ambiguous and incoherent objects as unknown, while only having been trained on vehicles and vulnerable road users. This is achieved thanks to an evidential reformulation of generalized logistic regression classifiers, and an online filtering strategy based on statistical assumptions. The training and testing were realized on LIDAR objects which were labelled in a semi-automatic fashion, and collected in different situations thanks to an autonomous driving and perception platform

Classification crédibiliste d'objets LIDAR en monde ouvert, par apprentissage profond

National audienceWe propose an evidential end-to-end deep neural network to classify LIDAR objects. The system is capable of classifying ambiguous and incoherent objects as unknown, while only having been trained on vehicles and vulnerable road users. This is achieved thanks to an evidential reformulation of generalized logistic regression classifiers, and an online filtering strategy based on statistical assumptions.Nous proposons un système de classification crédibiliste d'objets LIDAR par apprentissage profond. L'algorithme proposé est basé sur une reformulation crédibiliste d'un perceptron multi-couche, ainsi que sur un mécanisme de filtrage statistique simple. Le système, qui n'est entraîné que sur une base d'usagers routiers, est cependant capable de classifier des objets incohérents vis-à-vis de ce jeu d'entraînement comme étant des objets inconnus

Early-onset ventilator-associated pneumonia in adults randomized clinical trial: comparison of 8 versus 15 days of antibiotic treatment

International audiencePurposeThe optimal treatment duration for ventilator-associated pneumonia is based on one study dealing with late-onset of the condition. Shortening the length of antibiotic treatment remains a major prevention factor for the emergence of multiresistant bacteria.ObjectiveTo demonstrate that 2 different antibiotic treatment durations (8 versus 15 days) are equivalent in terms of clinical cure for early-onset ventilator-associated pneumonia.MethodsRandomized, prospective, open, multicenter trial carried out from 1998 to 2002.MeasurementsThe primary endpoint was the clinical cure rate at day 21. The mortality rate was evaluated on days 21 and 90.Results225 patients were included in 13 centers. 191 (84.9%) patients were cured: 92 out of 109 (84.4%) in the 15 day cohort and 99 out of 116 (85.3%) in the 8 day cohort (difference = 0.9%, odds ratio = 0.929). 95% two-sided confidence intervals for difference and odds ratio were [−8.4% to 10.3%] and [0.448 to 1.928] respectively. Taking into account the limits of equivalence (10% for difference and 2.25 for odds ratio), the objective of demonstrative equivalence between the 2 treatment durations was fulfilled. Although the rate of secondary infection was greater in the 8 day than the 15 day cohort, the number of days of antibiotic treatment remained lower in the 8 day cohort. There was no difference in mortality rate between the 2 groups on days 21 and 90.ConclusionOur results suggest that an 8-day course of antibiotic therapy is safe for early-onset ventilator-associated pneumonia in intubated patients

An international tool to measure perceived stressors in intensive care units: the PS-ICU scale.

Background The intensive care unit is increasingly recognized as a stressful environment for healthcare professionals. This context has an impact on the health of these professionals but also on the quality of their personal and professional life. However, there is currently no validated scale to measure specific stressors perceived by healthcare professionals in intensive care. The aim of this study was to construct and validate in three languages a perceived stressors scale more specific to intensive care units (ICU). Results We conducted a three-phase study between 2016 and 2019: (1) identification of stressors based on the verbatim of 165 nurses and physicians from 4 countries (Canada, France, Italy, and Spain). We identified 99 stressors, including those common to most healthcare professions (called generic), as well as stressors more specific to ICU professionals (called specific); (2) item elaboration and selection by a panel of interdisciplinary experts to build a provisional 99-item version of the scale. This version was pre-tested with 70 professionals in the 4 countries and enabled us to select 50 relevant items; (3) test of the validity of the scale in 497 ICU healthcare professionals. Factor analyses identified six dimensions: lack of fit with families and organizational functioning; patient- and family-related emotional load; complex/at risk situations and skill-related issues; workload and human resource management issues; difficulties related to team working; and suboptimal care situations. Correlations of the PS-ICU scale with a generic stressors measure (i.e., the Job Content Questionnaire) tested its convergent validity, while its correlations with the Maslach Burnout Inventory-HSS examined its concurrent validity. We also assessed the test–retest reliability of PS-ICU with intraclass correlation coefficients. Conclusions The perceived stressors in intensive care units (PS-ICU) scale have good psychometric properties in all countries. It includes six broad dimensions covering generic or specific stressors to ICU, and thus, enables the identification of work situations that are likely to generate high levels of stress at the individual and unit levels. For future studies, this tool will enable the implementation of targeted corrective actions on which intervention research can be based. It also enables national and international comparisons of stressors’ impact.post-print925 K

Prognosis of cirrhotic patients admitted to intensive care unit: a meta-analysis

and METAREACIR GroupInternational audienceBackgroundThe best predictors of short- and medium-term mortality of cirrhotic patients receiving intensive care support are unknown.MethodsWe conducted meta-analyses from 13 studies (2523 cirrhotics) after selection of original articles and response to a standardized questionnaire by the corresponding authors. End-points were in-ICU, in-hospital, and 6-month mortality in ICU survivors. A total of 301 pooled analyses, including 95 analyses restricted to 6-month mortality among ICU survivors, were conducted considering 249 variables (including reason for admission, organ replacement therapy, and composite prognostic scores).ResultsIn-ICU, in-hospital, and 6-month mortality was 42.7, 54.1, and 75.1%, respectively. Forty-eight patients (3.8%) underwent liver transplantation during follow-up. In-ICU mortality was lower in patients admitted for variceal bleeding (OR 0.46; 95% CI 0.36–0.59; p 19 at baseline (OR 8.54; 95% CI 2.09–34.91; p 26 (OR 3.97; 95% CI 1.92–8.22; p < 0.0001; PPV = 0.75), and hepatorenal syndrome (OR 4.67; 95% CI 1.24–17.64; p = 0.022; PPV = 0.88).ConclusionsPrognosis of cirrhotic patients admitted to ICU is poor since only a minority undergo liver transplant. The prognostic performance of general ICU scores decreases over time, unlike the Child–Pugh and MELD scores, even recorded in the context of organ failure. Infection-related parameters had a short-term impact, whereas liver and renal failure had a sustained impact on mortality

No effect of epoprostenol on right ventricular diameter in patients with acute pulmonary embolism: a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Right ventricular dilatation in the setting of acute pulmonary embolism is associated with an adverse prognosis. Treatment with a pulmonary vasodilator has never been studied systematically. We evaluated the effect of epoprostenol on right ventricular diameter and function in patients with acute pulmonary embolism and right ventricular dilatation.</p> <p>Methods</p> <p>In a randomized, single-blind study, 14 patients with acute pulmonary embolism received epoprostenol or placebo infusion for 24 hours on top of conventional treatment. Effects on right ventricular end-diastolic diameter, systolic pulmonary artery pressure, right ventricle fractional area changeand tricuspid annular plane systolic excursion were assessed by serial echocardiography. Furthermore Troponin T and NT-proBNP were measured serially.</p> <p>Results</p> <p>Compared to placebo, epoprostenol was associated with a relative change from baseline in right ventricular end-diastolic diameter of +2% after 2.5 hours and -8% after 24 hours. Epoprostenol did not have a significant effect on systolic pulmonary artery pressure, right ventricular fractional area change and tricuspid annular plane systolic excursion, nor on biochemical parameters.</p> <p>Conclusion</p> <p>In patients with acute pulmonary embolism and right ventricular overload, treatment with epoprostenol did not improve right ventricular dilatation or any other measured variables of right ventricular overload.</p> <p>Trial Registration</p> <p><it>Registration</it>: URL: NCT01014156</p> <p><it>Medical ethical committee</it>: Medisch-ethische toetsingscommissie (METc) from the VUmc (free university medical centre)</p

PathFinder 2015

担当教員:姉川雄大平成27年度(2015)教養展開科目(国際コア関連),授業コード:Ｇ15N1060