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The work described in this paper focuses on the impact of thermal aging on NOx trap structure and functions. They were evaluated on a Synthetic Gas Bench (SGB) and correlated with the analysis of the structural and chemical evolution of the catalyst. A FTIR Operando study allowed to further analyse the mechanisms occurring on the catalyst surface and highlight the most critical points. NOx trap samples were hydrothermally aged in a furnace up to 900°C under an oxidising flow. The main following impacts on the material were highlighted: reduction of the surface area, sintering of Pt yielding a decrease of the NO oxidation efficiency and hence of the NOx storage capacity, and a loss of CO and HC conversion, barium structural evolution into BaAl2O4 also being partly responsible for the loss of NOx storage capacity. Other possibilities for loss of NSC are: the transition of -Al2O3 to -Al2O3 and the evolution of Ba crystalline structure which needs further analysis. Both XRD and surface IR Operando studies show that hydrothermal aging has a rather homogeneous impact on all materials: alumina phase transition and BaAl2O4 production, which all lead to a partial decrease of all storage sites. L’étude suivante porte sur l’impact du vieillissement thermique sur la structure et les fonctions d’un piège à NOx. Les essais ont été réalisés sur un banc gaz synthétiques (BGS) et les résultats ont été corrélés à des analyses structurale et chimique du catalyseur. Une étude FTIR Operando a permis de mieux analyser les mécanismes se produisant sur la surface du catalyseur et de mettre en évidence les points les plus critiques. Des échantillons ont été vieillis hydrothermiquement à 900 °C sous un flux oxydant. Les principaux impacts ont été les suivants : la réduction de la surface spécifique, le frittage du Pt qui mène à une diminution de l’efficacité d’oxydation de NO, CO, HC et de la capacité de stockage, la formation de BaAl2O4 est en partie responsable de la perte de capacité de stockage de NOx. D’autres possibilités pour la perte de NSC sont : la transition de la -Al2O3 à la -Al2O3 et l’évolution de la structure cristalline du baryum qui demande des analyses approfondies. Les études DRX et Operando IR montrent que le vieillissement hydrothermique a un impact assez homogène sur tous les matériaux : la transition de phase de l’alumine et la formation de BaAl2O4, qui toutes mènent à une diminution partielle de tous les sites de stockage.

A multiwave non‐orographic gravity wave (GW) scheme is adapted to represent waves of small intrinsic phase speed, inertial waves, and wave emission from all altitudes. This last change removes the launching altitude parameter, an arbitrary parameter systematically used in GW schemes. In offline calculations using reanalysis fields, these changes impose larger amplitude, saturated waves everywhere in the middle atmosphere, which produces more realistic GW vertical spectra than in previous configurations. The same scheme, tested online in the Laboratoire de Météorologie Dynamique Zoom (LMDz) general circulation model, performs at least as well as the operational non‐orographic GW scheme. Some modest benefits are seen, for instance, in the equatorial tilt with altitude of the winter jets in the middle atmosphere. Although the scheme includes the effects of inertial waves, which are detected in the mesosphere by different observational platforms, the configuration that gives a reasonable climatology in LMDz hinders their vertical propagation and limits their presence at mesospheric altitudes. Plain Language Summary: Gravity waves are fluctuations in the atmosphere (seen in the temperature, wind velocity, and pressure fields) that transport energy and momentum from their sources in the troposphere and lower stratosphere to their sinks in the middle atmosphere. This way they exert a profound influence on the global circulation. Due to their relative small spatial scales, atmospheric general circulation models do not explicitly resolve these waves, and their effects on the circulation resolved by the model need to be parameterized. Parameterizations of gravity waves generated by fronts and flow imbalances typically assume that wave sources are located at a certain vertical level in the troposphere, which is easy to implement but neglects the fact that these processes can occur at all altitudes in the atmosphere. In this study, we explore to which extent parameterizations of gravity wave due to fronts and flow imbalances can be improved by allowing waves to be emitted from all model levels. Our results show evidence of modest corrections of some model biases, and a clear improvement in the parameterized gravity waves energy spectra. Key Points: A non‐orographic gravity wave parameterization is improved by including inertial waves and sources at all model levelsThe parameterized energy spectrum becomes much closer to observationsA global model with the new parameterization performs well, and some biases are modestly alleviated [ABSTRACT FROM AUTHOR]

In low-seismicity areas such as Europe, seismic records do not cover the whole range of variable configurations required for seismic hazard analysis. Usually, a set of empirical models established in such context (the Mediterranean Basin, northeast U.S.A., Japan, etc.) is considered through a logic-tree-based selection process. This approach is mainly based on the scientist's expertise and ignores the uncertainty in model selection. One important and potential consequence of neglecting model uncertainty is that we assign more precision to our inference than what is warranted by the data, and this leads to overly confident decisions and precision. In this paper, we investigate the Bayesian model averaging (BMA) approach, using nine ground-motion prediction equations (GMPEs) issued from several databases. The BMA method has become an important tool to deal with model uncertainty, especially in empirical settings with large number of potential models and relatively limited number of observations. Two numerical techniques, based on the Markov chain Monte Carlo method and the maximum likelihood estimation approach, for implementing BMA are presented and applied together with around 1000 records issued from the RESORCE-2013 database. In the example considered, it is shown that BMA provides both a hierarchy of GMPEs and an improved out-of-sample predictive performance. [ABSTRACT FROM AUTHOR]

Copyright of Proges en Urologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a simple and original method in order to simulate the behaviour of AC to DC converters with Matlab-Simulink. This approach takes into account overlap phenomenon, continuous and discontinuous conduction mode. The AC to DC converter is presented as a block (voltage input and voltage output) which can be inserted in a complex structure. The simplicity and the low computing-time of this method make it an interesting alternative to the Matlab's Power-Systems toolbox and hybrid simulation with PSIM and Matlab. Simulations results for non-controlled and controlled converters are presented and compared to experimental results. [ABSTRACT FROM AUTHOR]

This paper presents simulation results and experimental set of a vector controlled induction machine where the speed information is routed to the control board using Power Line Communication (PLC) device on a classical sinusoidal 230 V AC grid. After presenting the control strategy and the principles of PLC transmission, the authors present simulation results taking into account the delay induced by speed measurement with PLC modems. The simulation results are then compared to the results given by experimental set. [ABSTRACT FROM AUTHOR]

Background and Purpose: The treatment of scleroderma-related digital ulcers is still a therapeutic challenge. The most effective drugs are prostacyclin analogues. However, their usage is limited to an intravenous route of administration and by their frequent side effects. The objective of this study was to test whether treprostinil, iloprost and epoprostenol can induce sustained vasodilatation in rats when delivered locally using cutaneous iontophoresis.Experimental Approach: Treprostinil, iloprost and epoprostenol were delivered by cathodal and anodal iontophoresis onto the hindquarters of anaesthesized rats (n= 8 for each group). Skin blood flow was quantified using laser Doppler imaging and cutaneous tolerance was assessed from day 0 to day 3.Key Results: Cathodal but not anodal iontophoresis of treprostinil (6.4 mM), iloprost (0.2 mM) and epoprostenol (1.4 mM) induced a significant and sustained increase in cutaneous blood flow. The effects of treprostinil and iloprost were significantly different from those of treprostinil vehicle. Only weak effects were observed when both drugs were applied locally without current. Skin resistance was unchanged in areas treated with prostacyclin analogues. Finally, skin tolerance was good, with no evidence of epidermal damage.Conclusions and Implications: Cathodal iontophoresis of treprostinil and iloprost increases cutaneous blood flow with a good local tolerance. The effects of cathodal iontophoresis of these drugs should be investigated in humans, as they could have potential as new local therapies for digital ulcers in patients with scleroderma. [ABSTRACT FROM AUTHOR]

Copyright of Revue de Stomatologie & de Chirurgie Maxillo-Faciale is the property of Masson SPA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the present study was to examine the ability of the critical velocity (CV) and the endurance index (El) to assess endurance performance during intermittent exercise. Thirteen subjects performed two intermittent runs: 15-s runs intersected with 15s of passive recovery (15/15) and 30-s runs with 30-s rest (30/30). Runs were performed until exhaustion at three intensities (100,95 and 90% of the speed reached at the end of the 30-15 intermittent fitness test, VIFT) to calculate i) CV from the slope of the linear relationship between the total covered distance and exhaustion time (ET) (iCV): ii) anaerobic distance capacity from the y-intercept of the distance/duration relationship (iADC); and iii) El from the relationship between the fraction of VIFT at which the runs were performed and the log-transformed ET (iEI). Anaerobic capacity was indirectly assessed by the final velocity achieved during the Maximal Anaerobic Running Test (VMART). ET was longer for 15/15 than for 30/30 runs at similar intensities. iCV15/15 and iCV30/30 were not influenced by changes in ET and were highly dependent on VIFT. Neither iADC15/15 nor iADC30/30 were related to VMART. In contrast, iEI15/15 was higher than iEI30/30, and corresponded with the higher ET. In conclusion, only iEI estimated endurance capacity during repeated intermittent running. [ABSTRACT FROM AUTHOR]

The aim of the study was to test the hypothesis of the involvement of type II fibres in the `202 slow component phenomenon by using two prior fatiguing protocols on the knee extensor muscles. Nine subjects performed three constant-load cycling exercises at a work rate corresponding to 80% of their VO2 max: (i) preceded by a 20-min fatiguing protocol using electromyo-stimulation (EMS), (ii) preceded by a 20-min fatiguing protocol using voluntary contractions (VOL), and (iii) without fatiguing protocol (NFP). Voluntary and evoked neuromuscular properties of the knee extensor muscles were tested before (PRE) and after (POST) the two fatiguing protocols. Results show a significant reduction in voluntary force after both fatiguing protocols (- 19.9% and - 11.8%, in EMS and VOL, respectively p <0.01). After EMS, this decrease was greater than after VOL (p <0.05) and was combined with a slackening of muscle contractile properties which was absent after VOL (p < 0.05). Regarding the effects on oxygen uptake kinetics, the appearance of the slow component was delayed after EMS and its amplitude was lower than those obtained in VOL and NFP conditions (0.48±0.07 vs. 0.75±0.09 and 0.69±0.08 L·min-1, respectively; p<0.05). It can thus be concluded that exercises dedicated to preferentially fatiguing type II fibres may alter VO2 kinetics. [ABSTRACT FROM AUTHOR]

Ovarian cancers mostly derive from the monolayer epithelium that covers the ovary. There are currently very few molecular clues to the etiology of this cancer. Bone morphogenetic proteins (BMPs) are required for follicular development and female fertility and are expressed in the ovarian surface epithelium (OSE). We previously reported the expression of human chordin (CHRD), a BMP extracellular regulator, in the ovary. Here we show that CHRD is underexpressed in epithelium ovary cancer and epithelial cancer cell lines as compared with normal tissues and OSE, respectively. Besides, we detected BMP expression in all ovarian cell lines analyzed. To determine the functional relevance of the absence of CHRD mRNA in tumors and cancer cell lines, we studied the effects of CHRD on two cancer cell lines, BG1 and PEO14. Migratory and invasive properties were greatly reduced, whereas cell adhesion to the support was enhanced. In addition, we detected chordin (Chrd) expression in OSE of rat ovaries in a pattern similar to that of BMP4. Altogether, these results suggest that CHRD could participate in regulating BMP activity in normal OSE physiology, and that its mis-expression in OSE may facilitate cancer incidence and/or progression. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the performances of a combined ozone/anaerobic digestion system for waste activated sludge reduction. The objective was the estimation of the process efficiency and stability when keeping constant influent flow while increasing recycled chemically treated flow. The ozonation step consisted in a partial oxidation (0.16 g O3/g SS) of the anaerobic mesophilic digested sludge. Chemical treatment of digested sludge resulted in a threefold COD solubilization and a decrease of SS of 22%. Some of the advantages of digested sludge ozonation were: deodorization, better settlement and a reduction in viscosity. However there were drawbacks: foaming during ozonation and, at high ozone doses, poorer filterability. The anaerobic digestion was carried out over 6 months with an increasing recycling of ozonated flow. Suspended solids removal rate and COD removal rate were compared with initial operating conditions for the biological reactor and the whole combined process. The optimum recycling rate was 25% with increases of SS removal and COD removal of 54% and 66% respectively when considering the combined process; corresponding to a decrease of the hydraulic retention time from 24 days to 19 days. [ABSTRACT FROM AUTHOR]