A large time-step and well-balanced Lagrange-Projection type scheme for the shallow-water equations

This work focuses on the numerical approximation of the Shallow Water Equations (SWE) using a Lagrange-Projection type approach. We propose to extend to this context recent implicit-explicit schemes developed in the framework of compressibleflows, with or without stiff source terms. These methods enable the use of time steps that are no longer constrained by the sound velocity thanks to an implicit treatment of the acoustic waves, and maintain accuracy in the subsonic regime thanks to an explicit treatment of the material waves. In the present setting, a particular attention will be also given to the discretization of the non-conservative terms in SWE and more specifically to the well-known well-balanced property. We prove that the proposed numerical strategy enjoys important non linear stability properties and we illustrate its behaviour past several relevant test cases

Shape sensitivity analysis in aerodynamics using an isogeometric Discontinuous Galerkin method

International audienceThe sensitivity equation method aims at estimating the derivative of the solution of partial differential equations with respect to a parameter of interest. The objective of this work is to investigate the ability of an isogeometric Discontinuous Galerkin (DG) method to evaluate accurately sensitivities with respect to shape parameters originating from Computer-Aided Design (CAD), in the context of compressible aerodynamics. The isogeometric DG method relies on Non- Uniform Rational B-Spline representations, which allow to define a high-order numerical scheme for Euler/Navier-stokes equations, fully consistent with CAD geometries. We detail how this formulation can be exploited to construct an efficient and accurate approach to evaluate shape sensitivities. A particular attention is paid to the treatment of boundary conditions for sensitivities, which are more tedious in the case of geometrical parameters. The proposed methodology is first verified on a test- case with analytical solution and then applied to two more demanding problems, that concern the inviscid flow around an airfoil with its camber as shape parameter and the unsteady viscous flow around a three-element airfoil with the positions of slat and flap as parameters

Gasometria e hematologia de potros nascidos de éguas com placentite ascendente.

The ascending placentitis is a major cause of premature birth, abortion and birth of compromised foals, may cause hypoxia, and neonatal sepsis. The blood gas and hematology analysis provide important for monitoring the health of foals born to mares with ascending placentitis. The aim of this study is to evaluate the hematology and blood gas values of foals born to mares with ascending placentitis. Nine foals were used and divided into the following groups: three foals born to mares with natural placentitis infection and without treated (group I); four foals born to mares with experimentally induced placentitis and treated (group II); and two foals born to normal mares (group III). For the gas analysis blood samples were collected in three moments 0, 12 and 24 hours after birth, and analyzed pH, PO2, PCO2, HCO3-, EB and SO2. For the hematology blood samples were collected 0, 12, 24, 48 and 72 hours after birth and evaluated the red cells, white cells, fibrinogen and total plasma protein. The pH, EB and HCO3- don t differ between groups. Low PO2 (p=0,0132) in T12 in group I and II compared to group III represent due to placental changes, low capacity of pulmonary oxygenation and hypoxemia. PCO2 did not differ among three groups at T24, representing homogenous PCO2 values 24 hours after birth. PCO2 values presents an adaptive and compensatory response of foals from group II and faster when compared to group I, demonstrating a pH T0 reduced in both groups (I and II) when compared to group III and T24 in the physiological limits; the PCO2 in group I in T24 presents increase to the other groups, characterized a respiratory acidosis without compensation. Observed in the 24 hours after birth groups I and II showed neutrophil/lymphocyte rate decreased, featuring prematurity and delayed adaptive response to extra uterine environment. Foals born to mares with ascending placentitis and untreated have higher blood gases and hematologic changes from the foals born to mares with ascending placentitis and treated, demonstrating a compensatory and slower adaptive response.Sem bolsaA placentite ascendente é uma das principais causas de parto prematuro, aborto e nascimento de potros comprometidos, podendo causar hipóxia, assim como septicemia neonatal. A análise gasométrica e hematológica fornecem informações importantes para o monitoramento da saúde de potros nascidos de éguas com placentite. O objetivo deste estudo foi avaliar os valores gasométricos e hematológicos de potros nascidos de éguas com placentite ascendente. Foram utilizados nove potros nascidos divididos nos seguintes grupos: três potros nascidos de éguas com infecção natural de placentite sem tratamento (Grupo I), quatro potros nascidos de éguas com placentite induzida experimentalmente e tratadas (Grupo II), e dois potros nascidos de éguas sem alteração na gestação, como grupo controle (Grupo III). As coletas de sangue foram efetuadas 0, 12 e 24 horas após o nascimento para gasometria e as variáveis analisadas foram pH, PO2, PCO2, HCO3-, BE e SO2. Para hematologia, as coletas foram 0, 12, 24, 48 e 72 horas após o nascimento, avaliando-se a série vermelha, células da série branca, fibrinogênio e proteínas plasmáticas totais. Os valores de pH, BE e HCO3 -não diferiram estatisticamente entre os grupos. Reduzido valor na PO2 (p=0.0132) no T12 nos grupos I e II em relação ao grupo III apresenta-se devido às alterações placentárias, representando baixa capacidade de oxigenação pulmonar e hipoxemi a. A PO2 nos três grupos não diferiu no T24, representando valores homogêneos da PO2 24 horas após o nascimento nos três grupos independente das alterações prévias. A PCO2 apresenta uma curva adaptativa e resposta compensatória dos potros do grupo II mais uniforme e rápida quando comparado ao grupo I, demonstrando um pH em T0 reduzido em ambos os grupo (I e II) quando comparado ao grupo III e em T24 nos limites fisiológicos aceitos; porém a PCO2 do grupo I no T24 apresenta aumento significativo relacionado aos demais grupos, caracterizando uma acidose respiratória sem compensação. Observou-se nas primeiras 24 horas após o nascimento os grupos I e II apresentaram relação neutrófilos/linfócitos diminuída, caracterizando prematuridade e resposta adaptativa ao meio extra-uterino retardada. Potros nascidos de éguas com placentite ascendente e não tratadas apresentam maiores alterações gasométricas e hematológicas em relação a potros nascidos de éguas com placentite ascendente e tratadas, demonstrando uma resposta compensatória e adaptativa mais lenta

Dynamics and distribution of bacterial and archaeal communities in oil-contaminated temperate coastal mudflat mesocosms

Mudflats are ecologically important habitats that are susceptible to oil pollution, but intervention is difficult in these fine-grained sediments, and so clean-up usually relies on natural attenuation. Therefore, we investigated the impact of crude oil on the bacterial, diatom and archaeal communities within the upper parts of the diatom-dominated sediment and the biofilm that detached from the surface at high tide. Biodegradation of petroleum hydrocarbons was rapid, with a 50 % decrease in concentration in the 0–2-mm section of sediment by 3 days, indicating the presence of a primed hydrocarbon-degrading community. The biggest oil-induced change was in the biofilm that detached from the sediment, with increased relative abundance of several types of diatom and of the obligately hydrocarbonoclastic Oleibacter sp., which constituted 5 % of the pyrosequences in the oiled floating biofilm on day 3 compared to 0.6 % in the non-oiled biofilm. Differences in bacterial community composition between oiled and non-oiled samples from the 0–2-mm section of sediment were only significant at days 12 to 28, and the 2–4-mm-sediment bacterial communities were not significantly affected by oil. However, specific members of the Chromatiales were detected (1 % of sequences in the 2–4-mm section) only in the oiled sediment, supporting other work that implicates them in anaerobic hydrocarbon degradation. Unlike the Bacteria, the archaeal communities were not significantly affected by oil. In fact, changes in community composition over time, perhaps caused by decreased nutrient concentration and changes in grazing pressure, overshadowed the effect of oil for both Bacteria and Archaea. Many obligate hydrocarbonoclastic and generalist oil-degrading bacteria were isolated, and there was little correspondence between the isolates and the main taxa detected by pyrosequencing of sediment-extracted DNA, except for Alcanivorax, Thalassolituus, Cycloclasticus and Roseobacter spp., which were detected by both methods

Frequency of Chlamydia trachomatis infection in cervical intraepithelial lesions and the status of cytological p16/Ki-67 dual-staining

Background: Chlamydia trachomatis (Ct) is not a disease subject to mandatory reporting in Brazil, and the prevalence rate of this genital infection varies according to the region in which studies are conducted, as well as by the detection technique employed. Ct has been associated with persistence of Human papillomavirus (HPV) infection and the facilitation of cervical carcinoma development. We evaluated the Chlamydia trachomatis infection and its association with cytology, p16/Ki-67 dual-stained cytology and cervical intraepithelial lesions status in a screening cohort in Brazil. Methods: This was a cross-sectional study of 1481 cervical samples from asymptomatic women aged 18 to 64. Samples were collected for liquid-based cytology and Ct detection by polymerase chain reaction. p16/Ki-67 double staining was performed on samples with abnormal cytology. Statistical analysis was by chi-square and likelihood-ratio tests. Odds ratio (OR) and 95% confidence intervals (95% CI) were determined. Results: The frequency of Ct was 15.6% and its presence was not associated with detection of p16/Ki-67 [OR = 1. 35 (0.5-3.4)]. There was also no association between abnormal cervical cytology and Ct-positivity [OR = 1.21 (0.46-3.2)]. Associations were observed between p16/Ki-67 and high-grade lesions detected by cytology and in biopsies [OR = 3.55 (1.50-8.42) and OR = 19.00 (0.6-7.2), respectively]. Conclusions: The asymptomatic women in our study had a high frequency of Ct infection but this was not associated with p16/Ki-67 detection in samples with abnormal cytology. The expression of p16/Ki-67 was highest in women with high-grade CIN (p = 0.003).info:eu-repo/semantics/publishedVersio

A NURBS-based Discontinuous Galerkin method for CAD compliant flow simulations

International audienceIn this work, we explain how a classical nodal Discontinuous Galerkin (DG) method for conservation laws can be modified to be geometrically exact with respect to CAD (Computer-Aided Design) data. The proposed approach relies on the use of rational Bézier elements, that can exactly match geometries defined by NURBS (Non-Uniform Rational B-Splines) after some basic transformations. It has been found convenient to use the same basis to describe the solution, yielding a so-called isogeometric formulation. The resulting method exhibits optimal convergence rates and facilitates couplings with geometry, e.g. for local refinement, shape sensitivity analysis, or moving computational domains. Illustrations are provided for two-dimensional compressible Euler and Navier-Stokes equations

Understanding multivalent effects in glycosidase inhibition using C-glycoside click clusters as molecular probes

The synthesis of the first examples of multivalent C-glycosides based on C60-fullerene or β-cyclodextrin cores by way of Cu(I)-catalyzed azide–alkyne cycloadditions is reported. These compounds were designed as molecular probes to understand the mechanisms underlying the outstanding multivalent effects observed in glycosidase inhibition. The inhibition results obtained support a multivalent-binding model based on two scenarios both involving nonspecific interactions and varying by the presence or the absence of active site specific interactions. The magnitude of the multivalent effect obtained depends on the identity of the glycosidase involved and more specifically on the accessibility of its catalytic active site. Large inhibitory multivalent effects can be obtained when both glycosidase active sites and non-catalytic sites at the protein surface are involved in binding events. On the other hand, nonspecific interactions alone are not sufficient to achieve relative affinity enhancements exceeding a simple statistical effect (i.e., a relative inhibition potency not better than one on a valence-corrected basis).Ministerio de Economía y Competitividad de España (MINECO) y Fondos Europeos de Desarrollo Regional (FEDER y FSE). SAF2013-44021-

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Seroprevalence of Trypanosoma cruzi in a population of pregnant women and evaluation of their knowledge about Chagas Disease and its vectors

This study aimed at determining prevalence of anti-Trypanosoma cruzi antibodies in pregnant women in the extreme south of Brazil and at evaluating their knowledge about Chagas Disease (CD) and its vectors. The study was carried out in Pelotas, Rio Grande do Sul (RS) state, Brazil. The Chemiluminescent Microparticle Immunoassay (CMIA) was used for the triage and, when it was reagent, results were confirmed by the Indirect Immunofluorescence Assay (IFA). A semi-structured questionnaire was applied to evaluate patients’ knowledge. The Chi-squared test was used for evaluating correlations among variables under study while an Odds Ratio was conducted when associations were statistically significant. Only 33 (27.7%) out of 119 pregnant women under investigation underwent the serological test to identify T. cruzi because the study was carried out in the worst phase of the COVID-19 pandemic. However, prevalence was 6.1% (2 cases). Only 26.9% of pregnant women were able to identify triatominae and 66.4% did not know that the heart could be affected by CD. Associations between variables “lived/have lived in a rural area” and “having found ‘kissing bugs’ in the household”; “high schooling level” and “knowing that CD causes heart disorders”; and “stating that they know what CD is” and “identifying triatominae” exhibited statistical significance. Results showed that the rate of positive pregnant women is high and needs attention, even though the size of the sample is a limiting factor. Besides, the patients’ lack of knowledge about the disease and its vectors shows the importance of educational interventions