Development of error criteria for adaptive multi-element polynomial chaos approaches

International audienceThis paper presents and compares different methodologies to create an adaptive stochastic space partitioning in polynomial chaos applications which use a multi-element approach. To implement adaptive partitioning, Wan and Karniadakis first developed a criterion based on the relative error in local variance. We propose here two different error criteria: one based on the residual error and the other on the local variance discontinuity created by partitioning. The methods are applied to classical differential equations with long-term integration difficulties, including the Kraichnan–Orszag three-mode problem, and to simple linear and nonlinear mechanical systems whose stochastic dynamic responses are investigated. The efficiency and robustness of the approaches are investigated by comparison with Monte-Carlo simulations. For the different examples considered, they show significantly better convergence characteristics than the original error criterion used

Caractérisation d'aquifères régionaux en socle rocheux à partir de mines souterraines

Ce projet vise à développer une méthodologie pour caractériser les aquifères régionaux en socle rocheux fracturé et faillé à partir de mines souterraines, en considérant l’accès privilégié qu’offrent les mines et malgré les perturbations qu’elles engendrent. Les mines Beaufor, CANMET et Lac Herbin ont servi à tester les méthodes ; elles sont toutes situées dans le pluton de Bourlamaque, près de la ville de Val-d’Or, en Abitibi, au Québec, Canada. Les aspects suivants sont considérés : les systèmes de fractures, les propriétés hydrauliques, l’hydrogéochimie et les contraintes géomécaniques. Les industries minières possèdent plusieurs données existantes aidant à caractériser les aquifères rocheux. Des levés structuraux, des mesures de pression d’eau et l’échantillonnage de l’eau pour les analyses chimiques à partir des excavations minières complètent les données contribuant à établir un portrait de ces aquifères. Les levés de fractures montrent que même si les trois mines sont dans un contexte géologique similaire, elles sont différentes du point de vue structural. Plusieurs modèles analytiques de l’écoulement des eaux souterraines peuvent être utilisés à partir de données collectées dans les excavations souterraines pour estimer les propriétés hydrauliques d’un aquifère régional dans le roc fracturé. Ces modèles ont été développés soit pour des mines, pour des tunnels ou pour des puits à drains rayonnants. Les valeurs de conductivité hydraulique obtenues à l’aide de ces modèles pour les trois sites miniers sont présentées par des intervalles de valeurs possibles associés à chaque méthode ; les valeurs les plus probables sont situées entre 1,6 x 10-9 m/s et 4,6 x 10-9 m/s, les valeurs extrêmes sont de 2,0 x 10-10 m/s et 4,4 x 10-8 m/s. Les analyses chimiques de l’eau souterraine montrent deux types d’eau principaux : des eaux bicarbonatées calciques échantillonnées à des profondeurs allant de 0 à 195 m, et des eaux chlorurées sodiques potassiques à une profondeur supérieure à 300 m. La chimie de l’eau varie aussi d’un secteur à l’autre dans une même mine. La concentration en tritium diminue également avec la profondeur, ce qui tend à indiquer que les eaux profondes sont les plus vieilles. Les carbonates passent de sous-saturés près de la surface à saturés en profondeur puisque le pH augmente avec la profondeur, alors que pour les minéraux argileux c’est l’inverse. En conclusion, malgré les perturbations occasionnées par les mines, ces excavations représentent des endroits propices et comportant plusieurs avantages pour conduire des études de caractérisation d’aquifères en milieu rocheux fracturé et faillé

Shedding Light on the lifestyle and participation of portuguese adolescents with chronic conditions—Data from the HBSC 2018 Study

Variables associated with lifestyle can constitute either risk or protective factors for the development and progression of chronic conditions (CC). This study intends to explore the differences between adolescents with and without CC and between adolescents whose school participation is affected/not affected by the existing CC with regard to variables related to lifestyle (i.e., sleep, physical activity, BMI, and leisure). In addition, it also intends to analyze the influence of these variables (i.e., CC and lifestyle) regarding the adolescents’ quality of life (QoL). This work is part of the Portuguese HBSC 2018 study. A total of 8215 adolescents participated (52.7% female), with an average age of 14.36 years (SD = 2.28). The results showed that the adolescents with CC and whose school attendance and participation are affected by their CC exhibit more sleep difficulties (i.e., they experience lower sleep quality and have a higher degree of sleepiness), higher BMI levels (i.e., higher values of overweight and obesity), less participation in leisure activities, and a lower perception of QoL. A higher perception of QoL is associated with school participation unaffected by the existing CC, sleeping well, a low level of sleepiness, a more frequent practice of physical activity, a lower BMI, and a greater involvement in leisure activities. Adolescent health and well-being are a prominent issue in terms of public policies, with behavior and lifestyle playing a significant role in this domain. This message needs to be reinforced in regard to families, educators, healthcare professionals, and public sector policies, particularly concerning students with CC.info:eu-repo/semantics/publishedVersio

Multi-Color Imaging of Magnetic Co/Pt Multilayers

We demonstrate for the first time the realization of a spatial resolved two color, element-specific imaging experiment at the free-electron laser facility FERMI. Coherent imaging using Fourier transform holography was used to achieve direct real space access to the nanometer length scale of magnetic domains of Co/Pt heterostructures via the element-specific magnetic dichroism in the extreme ultraviolet spectral range. As a first step to implement this technique for studies of ultrafast phenomena we present the spatially resolved response of magnetic domains upon femtosecond laser excitation

HIRA dependent H3.3 deposition is required for transcriptional reprogramming following nuclear transfer to Xenopus oocytes.

BACKGROUND: Nuclear reprogramming is potentially important as a route to cell replacement and drug discovery, but little is known about its mechanism. Nuclear transfer to eggs and oocytes attempts to identify the mechanism of this direct route towards reprogramming by natural components. Here we analyze how the reprogramming of nuclei transplanted to Xenopus oocytes exploits the incorporation of the histone variant H3.3. RESULTS: After nuclear transplantation, oocyte-derived H3.3 but not H3.2, is deposited on several regions of the genome including rDNA, major satellite repeats, and the regulatory regions of Oct4. This major H3.3 deposition occurs in absence of DNA replication, and is HIRA-and transcription-dependent. It is necessary for the shift from a somatic- to an oocyte-type of transcription after nuclear transfer. CONCLUSIONS: This study demonstrates that the incorporation of histone H3.3 is an early and necessary step in the direct reprogramming of somatic cell nuclei by oocyte. It suggests that the incorporation of histone H3.3 is necessary during global changes in transcription that accompany changes in cell fate.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Serine/Threonine Protein Phosphatase-Mediated Control of the Peptidoglycan Cross-Linking L,D-Transpeptidase Pathway in Enterococcus faecium

International audienceThe last step of peptidoglycan polymerization involves two families of unrelated transpeptidases that are the essential targets of ␤-lactam antibiotics. D,D-transpeptidases of the penicillin-binding protein (PBP) family are active-site serine enzymes that use pentapeptide precursors and are the main or exclusive cross-linking enzymes in nearly all bacteria. However, pepti-doglycan cross-linking is performed mainly by active-site cysteine L,D-transpeptidases that use tetrapeptides in Mycobacterium tuberculosis, Clostridium difficile, and ␤-lactam-resistant mutants of Enterococcus faecium. We have investigated reprogramming of the E. faecium peptidoglycan assembly pathway by a switch from pentapeptide to tetrapeptide precursors and bypass of PBPs by L,D-transpeptidase Ldt fm. Mutational alterations of two signal transduction systems were necessary and sufficient for activation of the L,D-transpeptidation pathway, which is essentially cryptic in wild-type strains. The first one is a classical two-component regulatory system, DdcRS, that controls the activity of Ldt fm at the substrate level. As previously described, loss of DdcS phosphatase activity leads to production of the D,D-carboxypeptidase DdcY and conversion of the pentapeptide into the tetrapeptide substrate of Ldt fm. Here we show that full bypass of PBPs by Ldt fm also requires increased Ser/Thr protein phos-phorylation resulting from impaired activity of phosphoprotein phosphatase StpA. This enzyme negatively controlled the level of protein phosphorylation both by direct dephosphorylation of target proteins and by dephosphorylation of its cognate kinase Stk. In combination with production of DdcY, increased protein phosphorylation by this eukaryotic-enzyme-like Ser/Thr protein kinase was sufficient for activation of the L,D-transpeptidation pathway in the absence of mutational alteration of pepti-doglycan synthesis enzymes

A novel de novo Myocilin variant in a patient with sporadic juvenile open angle glaucoma

Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.BACKGROUND: Glaucoma is a leading cause of irreversible blindness. Pathogenic variants in the Myocilin gene (MYOC) cause juvenile open angle glaucoma (JOAG) in 8-36% of cases, and display an autosomal dominant inheritance with high penetrance. Molecular diagnosis is important for early identification as therapies are effective in minimizing vision loss and MYOC variants can be associated to severe glaucoma. MYOC variants are usually inherited, however a fifth of carriers do not report a family history. The occurrence of de novo MYOC variants is currently unknown. CASE PRESENTATION: In this study we investigated a 14 year old male Caucasian patient diagnosed with JOAG, and no family history of glaucoma. A novel probably deleterious MYOC:p.(Pro254Leu) variant was identified in the index case. This variant was not present in the parents or the siblings. CONCLUSION: This is the second report of a de novo MYOC variant in a sporadic case of JOAG and it is currently unknown if this mechanism occurs more frequently. This finding emphasizes the importance of screening individuals with JOAG for MYOC mutations irrespective of a negative family history

Tuning the formal potential of ferrocyanide over a 2.1 V range

We report the synthesis and characterization of homoleptic borane adducts of hexacyanoferrate(II). Borane coordination blueshifts d–d transitions and CN IR and Raman frequencies. Control over redox properties is established with respect to borane Lewis acidity, reflected in peak anodic potential shifts per borane of +250 mV for BPh_3 and +350 mV for B(C_6F_5)_3. Electron transfer from [Fe(CN-B(C_6F_5)_3)_6]^(4−) to photogenerated [Ru(2,2′-bipyridine)_3]^(3+) is very rapid, consistent with voltammetry data. Coordination by Lewis acids provides an avenue for selective modification of the electronic structures and electrochemical properties of cyanometalates

Estimation of the number of seriously injured road users in France, 2006-2015

European Congress of Epidemiology, LYON, FRANCE, 04-/07/2018 - 06/07/2018Background The European Commission requests its member states to provide the number of serious road injuries, according to MAIS 3+=Maximum AIS 3+, where AIS=Abbreviated Injury Scale. This challenges in all countries the issue of under-reporting of road injuries in the official police data and the issue of using a medical trauma scale. Methods In France, as in most countries, police data provide the frequency of road casualties, but they suffer from large under-reporting and strong selection bias (on severity, mode of transport, etc). In the Rhone county (pop 1.6M inhabitants). Other data are available: a road trauma registry has been set up in 1996. It covers fatalities, hospitalized, and those attending the Emergency departments only. All injuries are directly coded into the Abbreviated Injury Scale, by the registry physician. At the Rhône county level, both databases are linked. Annually, on the 2006-2012 period, the police reports 2800 casualties, the road trauma registry 7400 by the registry and 1700 are identified as common to both sources. A capture-recapture approach is then used, so that we can estimate the real number of road casualties (in the Rhône). More importantly the corrections factors between the police data and the estimated real subgroup of road causalities in the Rhône. In particular, to account for some conditions for applying capture-recapture, a multivariate model is used, including the variables that are associated with lower probability of reporting by the police: type of police, road network, severity measured by hospitalised (yes/no), MAIS3+, road user type (pedestrian, cyclist, car occupant...), whether the crash involved a crash opponent or not, etc. The police correction factors are finally applied to the national police data with the assumption that police recording practices are rather homogenous across France, by type of police force, and type of road casualties, This corresponds to indirect standardization, not on age and sex as usual but on the characteristics influencing police reporting. Results The national number of injured road casualties, respectively for all severity, and for MAIS3+, are estimated at 285,000 and 24,000 resp. in 2015. The 2015 frequency of sMAIS3+ roadusers consists of 6850 motorized two-wheel users, 6500 car occupants, 3550 cyclists, 3500 pedestrians and 800 others (van, bus, truck users). This confirms the heavy burden suffered by Motorized two-wheel users. Moreover, they only account for 2% of traveled kilometers whereas car occupants account for 70% of traveled kilometers. Also, these results show a different pattern than the number of fatalities, where it is the number of killed car occupants that is the highest. Conclusions The frequency of injured road users, all severities, has been confirmed by other sources, namely: the French national Travel Survey, and by the annual firemen data (they provide first aid on crash scene). Concerning the number of seriously injured road users, the ratio of the number of MAIS3+ casualties divided by the number of fatalities enables country to country comparison