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11.
Although traditional approaches to code profiling help locate performance bottlenecks, they offer only limited support for removing these bottlenecks. The main reason is the lack of detailed visual runtime information to identify and eliminate computation redundancy. We provide three profiling blueprints that help identify and remove performance bottlenecks. The structural distribution blueprint graphically represents the CPU consumption share for each method and class of an application. The behavioral distribution blueprint depicts the distribution of CPU consumption along method invocations and hints at method candidates for caching optimizations. The behavioral evolution blueprint compares profiles of different versions of a software system and highlights performance‐critical changes in the system. These three blueprints helped us to significantly optimize Mondrian, an open source visualization engine. Our implementation is freely available for the Pharo development environment and has been evaluated in a number of different scenarios. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
12.
BaTiO3 incorporation effect on the dielectric properties of polymer from aqueous emulsion: An enhanced dispersion technique 下载免费PDF全文
An economic and environment friendly process was adapted to synthesize new dielectric composite materials. Using ethylene vinyl acetate (EVA)/vinyl ester of versatic acid (VeoVa) terpolymer as an aqueous emulsion provides a homogenous dispersion of BaTiO3 (BT) particles, due to the high viscosity and polarity of the vinyl resin (VR). Composites films were obtained from these dispersions by water evaporation. The evolution of the dielectric properties as a function of the BaTiO3 content, was correctly fitted by a Maxwell‐Garnett model. This fitting of the experimental curve shows a good dispersion of filler in the vinyl resin and the particles separation by a layer of resin as expected for the preparation method used in this study. The VR/BT composites show good synergy between the dielectric properties of the different phases of the composites due to the formation of macrodipoles and to the strong interactions between polar EVA/VeoVa groups and the BaTiO3 particles surface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44333. 相似文献
13.
W. Taylor Shoulders Gregory Bizarri Edith Bourret Romain M. Gaume 《Journal of the American Ceramic Society》2016,99(1):20-26
Spray‐drying is an effective method for producing powder aggregates with controlled size and morphology. Here, we report on a systematic study aimed at determining how spray‐drying parameters such as nozzle temperature, gas flow, salt concentration and solution feed rate, influence the characteristics of BaCl2 granules prepared from aqueous solutions. We correlate the granule characteristics to these conditions through the use of processing maps and modeling. It is found that well‐dispersed, high density and spherical aggregates, which are favorable for subsequent powder compaction and sintering, can be obtained within a limited range of processing conditions. 相似文献
14.
Pierre-Jean Ferron Brendan Le Dar Julie Bronsard Clara Steichen Elodie Babina Romain Pelletier Thierry Hauet Isabelle Morel Karin Tarte Florian Reizine Bruno Clment Bernard Fromenty Thomas Gicquel 《International journal of molecular sciences》2022,23(1)
Using drugs to treat COVID-19 symptoms may induce adverse effects and modify patient outcomes. These adverse events may be further aggravated in obese patients, who often present different illnesses such as metabolic-associated fatty liver disease. In Rennes University Hospital, several drug such as hydroxychloroquine (HCQ) have been used in the clinical trial HARMONICOV to treat COVID-19 patients, including obese patients. The aim of this study is to determine whether HCQ metabolism and hepatotoxicity are worsened in obese patients using an in vivo/in vitro approach. Liquid chromatography high resolution mass spectrometry in combination with untargeted screening and molecular networking were employed to study drug metabolism in vivo (patient’s plasma) and in vitro (HepaRG cells and RPTEC cells). In addition, HepaRG cells model were used to reproduce pathophysiological features of obese patient metabolism, i.e., in the condition of hepatic steatosis. The metabolic signature of HCQ was modified in HepaRG cells cultured under a steatosis condition and a new metabolite was detected (carboxychloroquine). The RPTEC model was found to produce only one metabolite. A higher cytotoxicity of HCQ was observed in HepaRG cells exposed to exogenous fatty acids, while neutral lipid accumulation (steatosis) was further enhanced in these cells. These in vitro data were compared with the biological parameters of 17 COVID-19 patients treated with HCQ included in the HARMONICOV cohort. Overall, our data suggest that steatosis may be a risk factor for altered drug metabolism and possibly toxicity of HCQ. 相似文献
15.
Structural Analysis of Partial and Total Esters of Glycerol Undecenoate and Diglycerol Undecenoate 下载免费PDF全文
Gildas Nyame Mendendy Boussambe Romain Valentin Zéphirin Mouloungui 《Journal of the American Oil Chemists' Society》2015,92(11-12):1567-1577
The direct esterification reaction between glycerol and undecylenic acid or between diglycerol and undecylenic acid generates all the possible types of glycerol or diglycerol esters. Purification by silica gel chromatography resulted in the isolation of each of these types of ester in a pure form. The molecular structures of the compounds isolated were characterized and identified by mass spectrometry, 1H NMR, 13C NMR and DEPT‐135. We then studied the composition of esters of undecylenic acid formed with glycerol or diglycerol as a function of their reaction conditions, which constitute a highly complex system. We purified undecylenic acid esters from each polyol family to allow the structural identification of each ester of glycerol and each ester of diglycerol with undecylenic acid. We found that the polarity of these non‐ionic amphiphilic esters directly affected their affinity for organic and inorganic solvents and that these esters behaved very differently from anionic amphiphilic molecules, such as undecylenic acid. 相似文献
16.
Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
17.
Ole Becker Peter Sopade Romain Bourdonnay Peter J. Halley George P. Simon 《Polymer Engineering and Science》2003,43(10):1683-1690
The effect of an organically surface modified layered silicate on the viscosity of various epoxy resins of different structures and different functionalities was investigated. Steady and dynamic shear viscosities of the epoxy resins containing 0–10 Wt% of the organoclay were determined using parallel plate rheology. Viscosity results were compared with those achieved through addition of a commonly used micronsized CaCO3 filler. It was found that changes in viscosities due to the different fillers were of the same order, since the layered silicate was only dispersed on a micron‐sized scale in the monomer (prior to reaction), as indicated by X‐ray diffraction measurements. Flow activation energies at a low frequency were determined and did not show any significant changes due to the addition of organoclay or CaCO3. Comparison between dynamic and steady shear experiments showed good agreement for low layered silicate concentrations below 7.5 wt%, i.e. the Cox‐Merz rule can be applied. Deviations from the Cox‐Merz rule appeared at and above 10 wt%, although such deviations were only slightly above experimental error. Most resin organoclay blends were well predicted by the Power Law model, only concentrations of 10 wt% and above requiring the Herschel‐Buckley (yield stress) model to achieve better fits. Wide‐angle X‐ray measurements have shown that the epoxy resin swells the layered silicate with an increase in the interlayer distance of approximately 15 Å, and that the rheology behavior is due to the lateral, micron‐size of these swollen tactoids. 相似文献
18.
Romain Sainte Beuve Ken R. Morison 《Chemical Engineering and Processing: Process Intensification》2010
A hydrodynamic cavitation system based on a venturi was used to test the effectiveness of cavitation for enhancing the enzymatic hydrolysis of canola oil using lipase from Candida rugosa. Cavitation led to the production of fine oil-in-water and water-in-oil emulsions with the enzyme in the water phase. Using venturi inlet pressures of up to 8 bar, the yield of fatty acids was only about 60% of the maximum possible. In contrast, a simple stirred batch reactor produced over 90% of the maximum possible yield with reaction rates equal to, or better than, those obtained in a cavitating system. It was concluded that cavitation inhibited the reaction in some way and is not effective for intensification of hydrolysis. 相似文献
19.
This paper presents a newly developed method to estimate, in magnetic resonance (MR) images, the temperatures reached within the volume of an iceball produced by a cryogenic probe. Building on the direct measurements of the MR signal intensity and its correlation with independent temperature variations at the phase transition from liquid to solid, the thermal information embedded in the images was accessed. The volume and diameter of the growing iceball were estimated from a time series of MR images. Using regressions over the volume in the time and thermal domains, this method predicted the cryogenic temperatures beyond the range of sensitivity of the MR signal itself. We present a validation of this method in samples of gelatin and ex vivo pig liver. Temperature predictions are shown to agree with independent thermosensor readings over a range extending from 20 degrees C down to -65 degrees C, with an average error of less than 6 degrees C. 相似文献
20.
Hichem Abdessalam Boussad Abbès Yuming Li Ying-Qiao Guo Elvis Kwassi Jean-Luc Romain 《International Journal of Material Forming》2016,9(1):85-100
Numerical simulation of the polyurethane foaming process is a valuable method to analyze the molding process at an early stage of product development to shorten time-to-market cycles and cut costs by using fewer prototypes. However, this process involves highly coupled thermo-chemo-rheological modeling and needs adequate model parameters’ identification. A theoretical model including chemical reactions and thermo-rheological coupling of conservation equations was developed. Based on the theoretical model, three-dimensional numerical simulation for mold filling of the polyurethane foam was carried out by using Finite Pointset Method (FPM) to predict flow field, flow front advancement, temperature and density distributions during mold filling. A FOAMAT system was used to monitor foam height rise and reaction temperature on a cylindrical test tube and foam viscosity was measured by using a dynamic rotational rheometer with parallel-plate system. The parameters of the model were identified by an inverse analysis method which consists in determining the parameters by comparing the computed quantities to those measured experimentally. The overall modeling was validated by using short shot foams obtained with a panel mold cavity. Mold filling of an automotive underlay carpet cavity was investigated numerically. Flow front results were successfully compared to short shot foams obtained with the industrial mold cavity. 相似文献