Effect of Rainflow Cycle Number on Fatigue Lifetime of an Arm of a Vehicle Suspension System

Fatigue is considered as one of the main cause ofmechanical properties degradation of mechanical parts.Reliabilities methods are appropriate for fatigue analysis usinguncertainties that exist in fatigue material or process parameters.Current work aims the study of the effect of the Rainflow cyclenumber on fatigue lifetime of an upper arm of the vehiclesuspension system. The major part of the fatigue damage inducedin suspension arm is caused by two main classes of parameters.First parameter characterizes materials properties and a secondone describes equivalent force generated by road excitation andpassenger’s number. Therefore, representative sampling ofYoung's modulus and equivalent loading are selected as inputparameters to conduct repetitive finite elements simulations byMonte Carlo (MC) algorithm. Strain-life approach based onManson-coffin and Ramberg-Osgood equations is used in orderto determine fatigue lifetime of each combination of inputparameters. Thereafter, response surface is built according topreselected performance function. A PYTHON script wasdeveloped to automatize finite element simulations of the upperarm according to a design of experiments. Preliminary resultsshow Rainflow primary cycles to have significant effect onobtained cycle’s number to fracture. Load generated byexcitation road have a remarkable quasi-linear inverselyproportional effect on fatigue lifetime

Design and performance analysis of a regenerative evaporative cooler for cooling of buildings in arid climates

Evaporative cooling has been considered a low energy consumption process that often is associated with displacement ventilation and passive cooling strategies of buildings. While significant energy savings can be accrued from using evaporative cooling, there are many design challenges to improve the processes of heat and mass transfer and reduce design complexities. This paper seeks to advance the design of evaporative cooling through building and testing a novel regenerative evaporative cooler prototype. It proposes a design that integrates heat pipe and porous ceramic tube modules as an alternative to plate heat exchangers. The paper describes design arrangement of the cooler, a mathematical model and laboratory test results. Under controlled laboratory test conditions, the measured performance indices of wet bulb effectiveness, specific cooling capacity and coefficient of performance (COP) were determined as 0.8, 140 W per m2 of wet ceramic surface area and 11.43 respectively. Furthermore, experimental results show that under typical ambient conditions commensurate with that prevailing in arid climates, the cooler air supply temperature was as much as 14 oC below that of the ambient air

Résection laparoscopique d’une duplication gastrique chez l’adulte: traitement avec succès pour une pathologie rare

Les duplications de l'appareil digestif sont les malformations congénitales rares qui peuvent toucher tout  l'appareil digestive depuis la bouche jusqu' à l'anus. Certaines duplications sont asymptomatiques et sont diagnostiqués dans la plupart des cas pendant l'enfance. La prise en charge de la duplication gastrique est essentiellement chirurgicale. Le traitement de choix est l'exérèse complète de la duplication gastrique. Les auteurs rapportent un cas inhabituel de duplication gastrique complètement reséquée par laparoscopie. A notre connaissance, ceci est le premier cas d'une duplication gastrique traitée avec succès par laparoscopie dans la littérature Tunisienne. La Résection laparoscopique peut être ajoutée à l'arsenal thérapeutique dans le traitement chirurgical de duplications du tube digestif.Key words: Duplication, estomac, diagnostic, endoscopi

Computer modelling and experimental investigation of building integrated sub-wet bulb temperature evaporative cooling system

The paper presents computer modelling and laboratory experiment results of a sub-wet bulb temperature indirect evaporative cooling system for space cooling in buildings. The prototype employs hollow porous ceramic water containers as wet media material for water evaporation. The cooled air is delivered without increasing its moisture content. The performance of the cooler was evaluated using a computer model, and the results of which were validated experimentally. The cooling capacity and effectiveness of the cooler were evaluated at inlet air dry bulb temperature of 30 and 35°C and relative humidity ranging from 35% to 50%. It was found that the cooler can supply air for space cooling at sub-wet bulb temperature conditions; achieve measured cooling capacity approaching 225 W/m2 of exposed ceramic material wet surface area and wet bulb effectiveness higher than unity. The high thermal performance of the constructed evaporative cooler indicates the system could be a potential substitute to conventional mechanical air-conditioning systems in buildings in many parts of the world where hot and dry climatic conditions prevail

Lipid nanocapsules functionalized with polyethyleneimine for plasmid DNA and drug co-delivery and cell imaging

The paper reports on the preparation of lipid nanocapsules (LNCs) functionalized with poly(ethyleneimine) (PEI) moieties and their successful use as drug and gene delivery systems. The cationic LNCs were produced by a phase inversion process with a nominal size of 25 nm and subsequently modified with PEI chains using a transacylation reaction. The functionalization process allowed good control over the nanoscale particle size (26.2 ± 3.9 nm) with monodisperse size characteristics (PI < 0.2) and positive surface charge up to +18.7 mV. The PEI-modified LNCs (LNC25-T) displayed good buffering capacity. Moreover, the cationic LNC25-T were able to condense DNA and form complexes via electrostatic interactions in a typical weight ratio-dependent relationship. It was found that the mean diameter of LNC25-T/pDNA complexes increased to ∼40-50 nm with the LNC25-T/pDNA ratio from 1 to 500. Gel electrophoresis and cell viability experiments showed that the LNC25-T/pDNA complexes had high stability with no cytotoxicity due to the anchored PEI polymers on the surface of LNCs. Finally, the transfection efficiency of the LNC25-T/pDNA complexes was studied and evaluated on HEK cell lines in comparison with free PEI/pDNA polyplexes. The combination of cationic LNCs with pDNA exhibited more than a 2.8-fold increase in transfection efficiency compared to the standard free PEI/pDNA polyplexes at the same PEI concentrations. Moreover, we have demonstrated that LNC25-T/pDNA loaded with a hydrophobic drug, paclitaxel, showed high drug efficacy. The high transfection efficiency combined with the potential of simultaneous co-delivery of hydrophobic drugs, relatively small size of LNC25-T/pDNA complexes, and fluorescence imaging can be crucial for gene therapy, as small particle sizes may be more favorable for in vivo studies

Fast and facile preparation of nanostructured silicon surfaces for laser desorption/ionization mass spectrometry of small compounds

International audienceRATIONALE: Many important biological processes rely on specific biomarkers (such as metabolites, drugs, proteins or peptides, carbohydrates, lipids, ...) that need to be monitored in various fluids (blood, plasma, urine, cell cultures, tissue homogenates, …). Although mass spectrometry (MS) hyphenated to liquid chromatography (LC) is widely accepted as a 'gold-standard' method for identifying such synthetic chemicals or biological products, their robust fast sensitive detection from complex matrices still constitutes a highly challenging matter.METHODS: In order to circumvent the constraints intrinsic to LC/MS technology in terms of prior sample treatment, analysis time and overall method development to optimize ionization efficiency affecting the detection threshold, we investigated laser desorption/ionization mass spectrometry (LDI-MS) by directly depositing the sample under study onto cheap inert nanostructures made of silicon to perform straightforward sensitive and rapid screening of targeted low mass biomarkers on a conventional MALDI platform.RESULTS: The investigated silicon nanostructures were found to act as very efficient ion-promoting surfaces exhibiting high performance for the detection of different classes of organic compounds, including glutathione, glucose, peptides and antibiotics. Achieving such broad detection was compulsory to develop a SALDI-MS-based pre-screening tool.CONCLUSIONS: The key contribution of the described analytical strategy consists of designing inert surfaces that are fast (minute preparation) and cheap to produce, easy to handle and able to detect small organic compounds in matrix-free LDI-MS prerequisite for biomarkers pre-screening from body fluids without the recourse of any separation step

MoS 2 /TiO 2 /SiNW surface as an effective substrate for LDI-MS detection of glucose and glutathione in real samples

International audienc

Effect of Resveratrol on Pregnancy, Prenatal Complications and Pregnancy-Associated Structure Alterations

Adverse pregnancy outcomes are considered significant health risks for pregnant women and their offspring during pregnancy and throughout their lifespan. These outcomes lead to a perturbated in-utero environment that impacts critical phases of the fetus&rsquo;s life and correlates to an increased risk of chronic pathological conditions, such as diabetes, obesity, and cardiovascular diseases, in both the mother\u27s and adult offspring&rsquo;s life. The dietary intake of naturally occurring antioxidants promotes health benefits and disease prevention. In this regard, maternal dietary intake of polyphenolic antioxidants is linked to a reduced risk of maternal obesity and cardio-metabolic disorders, positively affecting both the fetus and offspring. In this work, we will gather and critically appraise the current literature highlighting the effect/s of the naturally occurring polyphenol antioxidant resveratrol on oxidative stress, inflammation, and other molecular and physiological phenomena associated with pregnancy and pregnancy conditions, such as gestational diabetes, preeclampsia, and preterm labor. The resveratrol impact on prenatal complications and pregnancy-associated structures, such as the fetus and placenta, will also be discussed. Finally, we will draw conclusions from the current knowledge and provide future perspectives on potentially exploiting resveratrol as a therapeutic tool in pregnancy-associated conditions

Effect of Resveratrol on Pregnancy, Prenatal Complications and Pregnancy-Associated Structure Alterations

Adverse pregnancy outcomes are considered significant health risks for pregnant women and their offspring during pregnancy and throughout their lifespan. These outcomes lead to a perturbated in-utero environment that impacts critical phases of the fetus’s life and correlates to an increased risk of chronic pathological conditions, such as diabetes, obesity, and cardiovascular diseases, in both the mother’s and adult offspring’s life. The dietary intake of naturally occurring antioxidants promotes health benefits and disease prevention. In this regard, maternal dietary intake of polyphenolic antioxidants is linked to a reduced risk of maternal obesity and cardio-metabolic disorders, positively affecting both the fetus and offspring. In this work, we will gather and critically appraise the current literature highlighting the effect/s of the naturally occurring polyphenol antioxidant resveratrol on oxidative stress, inflammation, and other molecular and physiological phenomena associated with pregnancy and pregnancy conditions, such as gestational diabetes, preeclampsia, and preterm labor. The resveratrol impact on prenatal complications and pregnancy-associated structures, such as the fetus and placenta, will also be discussed. Finally, we will draw conclusions from the current knowledge and provide future perspectives on potentially exploiting resveratrol as a therapeutic tool in pregnancy-associated conditions

Application of FSSIM in two test case regions to assess agro-environmental policies at farm and regional level. PD 6.3.2.2

SEAMLESS integrated project, EU 6th Framework Programme, contract no.010036-2.This deliverable presents the results of the first application of the bioeconomic farm model FSSIM for a set of farm types representing the arable farming systems in two Test Case regions of the SEAMLESS-IP project: Midi-Pyrénées (France) and Sikasso (Mali). This application is performed through the FSSIM standalone version (i.e. outside the SEAMLESS-IF system) and it has two aims: (i) to test the capacity of FSSIM to capture the diversity of conditions from the North to the South, regarding biophysical and socio-economic aspects; and (ii) to provide a first example of assessment at the field and farm levels of the economic and ecological impacts of specific agricultural and environmental policies and technological innovations. The impact assessment at the field level was done through the biophysical model CropSyst, used as a substitute for APES, which is not yet operational for an application. FSSIM is a comparative static mathematical programming model which seeks to capture resource, socio-economic and policy constraints and the major farmer’s objectives. It was designed to be sufficiently generic and flexible to be applied for all relevant farming systems, easily transferable between different geographic locations, reusable and with a rich usage comfort. The simulated scenario in the French region (Midi-Pyrénées) is focused on the adoption of the Nitrate Directive (91/676/EC). The Nitrate Directive is an environmental measure designed to reduce water pollution by nitrate from agricultural sources and to prevent such pollution occurring in the future. The CropSyst-FSSIM-Indicators modelling chain was used to compare a baseline scenario driven by the CAP reform, and a policy scenario combining the CAP reform with the application of the Nitrate Directive and the adoption of alternative crop management. This modelling chain was operated “manually”, i.e. using specific databases filed by one component for the next one, but in a manner consistent with the future applications done inside SEAMLESS-IF when the modelling chains will be operational. The tested scenario in the Malian region (Sikasso) is based on the adoption of new cropping techniques, more efficient and suited to a wide range of socioeconomic and biophysical conditions. These techniques are usually designed at the plot level within research stations and sometimes in farmers’ plots. FSSIM was used in this scenario as a tool to assist and establish a dialogue between agronomic research and farmers, in order to help the adoption or design processes of these new cropping techniques. After a brief description of the FSSIM framework, particularly model design, specification and components (farm activities, resource constraints, policies specification and objective function etc.), sections 3 and 4 present the results of the application for the two Test Case regions respectively. Each section exposes the context, the tested scenarios, the required input data, the procedure followed for running the model (i.e. specification of components, modules and calibration procedure used) and the results of the application. The conclusions, in relation to the comparison of the scenarios and the implications for future FSSIM development and integration into SEAMLESS-IF, are given in section