Aix-Marseille University Research Articles

Sharing a laugh at others: Humorous convergence in French conversation

The aim of this article is to clarify the fuzzy notion of “successful humour”. It focuses on humorous sequences in French face-to-face interactions which are both successful and have a same type of target: a collective “Other” (foreign culture, a French or foreign institution, a French or foreign socio-professional group). It will be shown that laughing about/at others (with all the aggressiveness this could imply) is not inconsistent with the necessary collaborative aspect of the conversation.On the contrary, the necessary collaboration between the participants will be highlighted through analysing humour in two different but complementary ways. Firstly, analysing humour through one specific target (the collective “Other”) will show that the participants rely on shared knowledge to display fictitious identities allowing them to construct humour. Secondly, a structural analysis of successful humorous sequences will deepen the notion of successful humour, highlighting two different structures: a two-part structure and a three-part structure. While the terms “successful humour” will be restricted to the former, the notion of “humorous convergence” will be proposed to refer to the latter.This study is based on 51 successful humorous sequences extracted from three face-to-face interactions audio- and video-recorded in an anechoic room at Aix-Marseille University, France

Correction to: Gas occurrence and shallow conduit systems in the Western Sea of Marmara: a review and new acoustic evidence

The original version of this article unfortunately contained a mistake. The affiliation of Pierre Henry should have been the following: Aix Marseille Univ, CNRS, IRD, INRA, Coll France, CEREGE, Aix-en-Provence, France. This correction was requested by Aix-Marseille University.

On the syntax of spoken French

AbstractThis paper gives an account of the research carried out by theGroupe Aixois de Recherche en Syntaxe(GARS, Aix-Marseille University), in the field of spoken French description. Our framework explicitly states the need for two independent but related levels of grammatical description, namely themicrosyntacticandmacrosyntacticlevels. Elaborating a twofold model has allowed us to propose a descriptive method differing from traditional sentence-based analyses, which raise considerable difficulties, especially in the domain of spoken language description. Regarding the “maximal-units” of syntactic description, our framework suggests that two different kinds of units should be postulated: Government-Units and Utterance-Units. The paper illustrates the distinction between the micro- and macro-syntactic components by introducing examples mostly drawn from spoken French corpora.

Environmental performance of universities: Proposal for implementing campus urban morphology as an evaluation parameter in Green Metric

Over the last years, various sustainability evaluation tools for universities have been developed and have gained a certain diffusion. This paper reviews the applications of the most widespread university ranking index, Green Metric (GM) index, focusing on the analysis of its characteristics and its capability to assess how the campus urban morphology can affect the universities sustainability issues.Firstly, a new approach to classify University campuses, concerning urban morphology, was proposed by defining the Urban Morphology Index (UMI), which aims at classifying University campuses in homogeneous and comparable categories (compact campus VS diffuse campus). Then, an analysis of the 2016 GM index, supported by a comparison among data from literature and by analysing and comparing five case studies (Roma Tre University, Polytechnic of Turin, Aix Marseille University, Anglia Ruskin University and University of Nottingham), was carried out, showing how GM tool could penalize in terms of sustainability the diffuse campuses respect the compact ones. Finally, starting from a literature review of similar tools, in order to better evaluate the urban morphology effects in terms of sustainability rating, five new parameters (related to soil consumption, reuse of existing buildings, presence of existing public transport, public green areas and other services close to the universities) were proposed to be integrated in the GM tool.

Effect of phase space folding on the accuracy of the Berk–Breizman cubic equation

We assess the quantitative accuracy of the Berk–Breizman (BB) cubic wave equation that has been previously derived to describe the initial nonlinear behavior of kinetic instabilities (Berk et al 1996 Phys. Rev. Lett. 76 1256–9; Breizman et al 1997 Phys. Plasmas 4 1559–68; Berk et al 1997 Plasma Phys. Rep. 23 778–88). The fifth-order terms in the wave equation are calculated for the first time, which allow us to quantify this accuracy arbitrarily close to marginal stability. We find a relation between the breakdown of the quantitative accuracy of the cubic equation, occurring well below the instability’s saturation level, and the recently observed phase space folding effect (Idouakass 2016 PhD Thesis Aix-Marseille University). This effect emerges when the resonant particle distribution function (Ω is a momentum-like variable, φ is its conjugate variable, and t is the time) evolves from a (locally) single-valued function of φ, at fixed Ω, to a triple-valued one (i.e. there emerges a point in phase space where ).

Improvement of Secondary Metabolites from Phyllanthus odontadenius against Malaria by Mutagenesis

Aims: Majority of deaths in children aged under 5 years are due to Plasmodium falciparum malaria. Malaria deaths in children decreased but malaria remains a major killer of children, taking the life of a child every 2 minutes. This study aims to investigate the increasing of the in vitro antiplasmodial activities by mutagenesis techniques using gamma-rays (Cs-137) or sodium azide (NaN3) as utagens. It will allow the importance of mutagenesis use as tools for improvement of secondary metabolites against malaria parasites using chemical or physical mutagens. Study Design: Laboratory experiment tests : identification of plant material, immersion of seeds in SA (sodium azide) solutions or irradiation by Gamma-rays (Cs-137) of P. odontadenius seeds for improvement of secondary metabolites against malaria parasites, in vitro culture of seeds followed by the in situ culturing of plantlets for obtaining material of study, phytochemical screening of Phyllanthus odontadenius aerial parts to determine the change of compounds in comparison to controls, in vitro antiplasmodial tests for the determination of SA concentrations or those of gammarays doses which killing 50% of malaria parasite populations (IC50). Place and Duration of Study: Department of Biotechnology and Molecular Biology, Department of Biochemistry: General Atomic Energy Commission, Regional Nuclear Studies Center of Kinshasa, P.O. Box. 868 Kinshasa XI, Democratic Republic of the Congo (DRC). National Institute of Biomedical Research (NIBR) at Kinshasa/Gombe (DRC). Laboratory of UMR-MD3, Aix-Marseille University, Faculty of Pharmacy/Marseille, France. The experiments were conducted from Junuary - December 2010; August and December 2011 and during May and September 2012 until July 2014. Methodology: Aerial parts of plants M1 and M2 from Gamma-rays irradiation of P. odontadenius seeds or from immersion of P. odontadenius seeds in sodium azide solutions used as biological material for the in vitro antiplasmodial analysis. The in vitro antiplasmodial activities assays on clinical isolates of P. falciparum and on chloroquine-resistante P. falciparum strain K1 was determined using microscopic method, the isotopic micro-test method and using HRP2-based ELISA assay. Results: Gamma-rays (Cs-137) increased (multiplied) the in vitro antiplasmodial activities from 2.48 up to 7.6 in comparison to control. Thus, the in vitro antiplasmodial activities were improved or exceeded from 147.57% up to 660% than those of control plant. SA had increased (multiplied) the in vitro antiplasmodial activities from 1.24 up to 10.15 comparing to the control plants. The antiplasmodial activities in vitro were exceeded compared to the control plants from 24.43% up to 915%. Conclusion: Treatment of P. odontadenius seeds by Gamma-rays or by SA give plants high in vitro antiplasmodial activities. Values of in vitro antiplasmodial activities varried from 1.24 (147.57%) to 10.15 (915%). 125, 150 and 225 Gy of Gamma-rays (Cs-137) for physical mutagenesis and 10.15 and 17.5 M of SA solutions for the chemical mutagenesis could be used for improving in vitro antiplasmodial activities against P. falciparum (clinical isolates of P. falciparum or chloroquine-resistant P. falciparum strain K1). Thus, plants extracts from treated seeds have justified the usefulness of mutagens in plant breeding particularly in the increasing production of secondary metabolite against malaria parasite.

Macroparticles monitoring for biocontamination prevention

ABSTRACTThis study investigated a potential correlation between deposited macroparticles >5µm and bioaerosols. Bioaerosols were detected using both passive (culture plates) and dynamic sampling (biocollectors). Bioaerosols were then revealed visually on culture plates after incubation and counted in colony forming unit (CFU)/cm2. Macroparticles were counted on line by CLEAPART-100 (patent CEA – Aix Marseille University – Winlight System). It enables continuous monitoring of the deposit of macroparticles on surfaces. We have shown that those macroparticles could be strongly correlated to viable particle measurements (bacteria and mould) after dynamic sampling by biocollectors. As viable particle measurements require an incubation period of at least 48 hours, it is easy to understand the advantage in continuous macroparticle done by CLEAPART-100. CLEAPART-100 is therefore an instrument which enables the alert to be raised in relation to any contamination or biocontamination events.

Mesurer les dépenses d’APC : méthodologie et étude de cas

Souvent abusivement designe comme le modele « auteur-payeur », l’open access gold est generalement finance en amont par les institutions d’enseignement superieur et de recherche qui editent et diffusent les revues. De fait, le DOAJ (Directory of Open Access Journals) recense 67 % de revues en open access – dont la RFSIC – ne demandant aucun frais de publication aux auteurs. Le tiers de revues restant s’appuyant sur le paiement par les auteurs – ou leur institution de rattachement le plus souvent – de frais de traitement (Article Processing Charges, APC) pour assurer la diffusion ouverte des articles que celles-ci ont accepte de publier. A ces revues s’ajoutent les revues traditionnellement disponibles sur abonnement qui proposent une option de diffusion en open access a l’article : il s’agit du modele de l’open access « hybride ». Le suivi de l’evolution des couts engendres par l’open access gold aussi bien que par l’open access hybride suscite un interet depuis la fin des annees 2000. Il devient crucial dans certains pays (Royaume-Uni) a compter de 2012 et est desormais un enjeu reconnu a l’echelon europeen. Apres avoir presente l’etat de la reflexion europeenne dans le domaine du suivi des depenses d’APC, l’etude s’attache a presenter trois methodes de suivi qui peuvent etre mises en place au sein d’etablissements d’enseignement superieur et de recherche : utilisation d’une base de donnees bibliographique ; sollicitation des editeurs et recours au logiciel comptable. Ces methodes ont ete appliquees a deux universites (Aix-Marseille Universite et l’Universite de Lorraine) sur des donnees allant de deux a trois annees (2013-2015). L’article presente de premiers resultats qui permettent d’identifier et de discuter des forces et des faiblesses de chacune des approches methodologiques evoquees.

Extended inferior antrostomy for maxillary sinus surgery.

Clinical OtolaryngologyVolume 43, Issue 2 p. 786-788 TECHNICAL NOTE Extended inferior antrostomy for maxillary sinus surgery J. Michel, Corresponding Author J. Michel justin.michel@ap-hm.fr Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, France Correspondence J. Michel, Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille, France. Email: justin.michel@ap-hm.frSearch for more papers by this authorT. Radulesco, T. Radulesco orcid.org/0000-0002-5939-5372 Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, FranceSearch for more papers by this authorM. Penicaud, M. Penicaud Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, FranceSearch for more papers by this authorP. Dessi, P. Dessi Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, FranceSearch for more papers by this author J. Michel, Corresponding Author J. Michel justin.michel@ap-hm.fr Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, France Correspondence J. Michel, Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille, France. Email: justin.michel@ap-hm.frSearch for more papers by this authorT. Radulesco, T. Radulesco orcid.org/0000-0002-5939-5372 Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, FranceSearch for more papers by this authorM. Penicaud, M. Penicaud Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, FranceSearch for more papers by this authorP. Dessi, P. Dessi Department of Oto-Rhino-Laryngology and Head and Neck Surgery, Assistance Publique, Hôpitaux de Marseille, La Conception University Hospital, Marseille Cedex, France Aix-Marseille University, Marseille Cedex, FranceSearch for more papers by this author First published: 21 June 2017 https://doi.org/10.1111/coa.12924Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume43, Issue2April 2018Pages 786-788 RelatedInformation

Achieving a cure for hypothalamic hamartomas: aSisyphean quest?

Achieving a cure for hypothalamic hamartomas: aSisyphean quest?

UNDERWATER PHOTOGRAMMETRY, CODED TARGET AND PLENOPTIC TECHNOLOGY: A SET OF TOOLS FOR MONITORING RED CORAL IN MEDITERRANEAN SEA IN THE FRAMEWORK OF THE ”PERFECT” PROJECT

Abstract. PErfECT "Photogrammetry, gEnetic, Ecology for red coral ConservaTion" is a project leaded by the Laboratoire des Sciences de lInformation et des Systmes (LSIS - UMR 7296 CNRS) from the Aix-Marseille University (France) in collaboration with the Spanish National Agency for Scientific Research (CSIC, Spain). The main objective of the project is to develop innovative Tools for the conservation of the Mediterranean red coral, Corallium rubrum. PErfECT was funded by the Total Fundation. The adaptation of digital photogrammetric techniques for use in submarine is rapidly increasing in recent years. In fact, these techniques are particularly well suited for use in underwater environments. PErfECT developed different photogrammetry tools to enhance the red coral population surveys based in: (i) automatic orientation on coded quadrats, (ii) use of NPR (Non Photo realistic Rendering) techniques, (iii) the calculation of distances between colonies within local populations and finally (iv) the use of plenoptic approaches in underwater conditions.

Projet parental des internes de médecine générale d’Aix-Marseille université : connaissances théoriques en reproduction et attitude vis-à-vis de la parentalité

ObjectivesAnalyze residents’ intentions about parenting and knowledge about fertility, as well as their alleged behavior towards a diagnosis of diminished ovarian reserve. Materials and methodsProspective study with distribution of self-administered questionnaire to residents of Aix-Marseille university from June to September 2015. The questionnaire was composed of a first descriptive part including generic and personal informations about the residents and their intentions towards parenting. The second part was a 9 questions survey aimed at testing their knowledge about fertility and ovarian reserve and a final question placing them in a situation of a diminished ovarian reserve diagnosis in order to analyze their reactions. ResultsThe overall participation rate was 53.2%, including 220 women with an average age of 27 years (SD: 1.8 years) and 116 men with an average age of 27.3 years (SD: 2.2 years). The 11.8% of female residents (n=26) already had one or more children vs.6.9% of male residents (n=8). Among the residents without children, 99% of females (n=192) and 91.7% of males (n=99) said they wanted to have children in the future, planning an average age to have their first child of 29.6 years (SD: 1.9 years) for females and 30.4 years (SD: 2.2 years) for men. Moreover, 58.3% of female residents (n=112) and 53.5% of male residents (n=53) reported that they were postponing their plan to have children after the completion of their medical studies. In a simulation of couples facing a diagnosis of diminished ovarian reserve, 73.6% of females and 61.2% of males would be ready to change their life choices and conceive a baby sooner than originally planned. ConclusionAlmost all the general medicine residents have plannedto have children in the future and more than half of them postpone their parental plan after the end of their residency, although the decline of female fertility in relation to aging is widely known among them.

Supercritical CO2 extraction of essential oil from Algerian Argan (Argania spinosa L.) seeds and yield optimization

Supercritical CO2 extraction of essential oil from Argan (Argania spinosa L.) was carried out experimentally and the effect of operating parameters such as pressure and temperature on the extracting process was investigated, considering three different values for each parameter (100, 250, and 400 bar and 35, 45, 55 °C for pressure and temperature, respectively).The extraction process was optimized by means of an experimental design using the statistical software Nemrod-w available in laboratory M2P2, Aix-Marseille University, France. A second order polynomial was used to express the oil recovery yield using the response surface methodology (RSM) and the obtained results were very close to the experimental values with a correlation factor of 0.957, demonstrating once more the reliability of this technique. An optimal yield value of 75.83% was obtained at a pressure of 297.71 bar and a temperature of 317.78 K.Gas chromatography–Mass Spectrometry analyses were carried out on samples obtained at the optimal conditions (297.71 bar and 317.8 K) and showed that the major compounds were fatty acids such as Palmitic, Stearic, Oleic, Linoleic acids and squalene.

Diversification alimentaire du nourrisson. Évaluation des pratiques en regard des recommandations françaises actuelles chez les pédiatres varois et les internes affectés à la faculté d’Aix-Marseille

To assess the practices of pediatricians in relation to current recommendations of the French Society of Pediatrics on infant food diversification. This was an observational study conducted from 1 November 2014 to 31 March 2015. The study population consisted of 97pediatricians in the Var department and 84pediatric residents assigned to the University of Aix-Marseille in France. A questionnaire was sent by email or post to determine physician characteristics, food diversification methods in healthy children and those at atopic risk, and how the pediatric consultation was conducted. The expected answers were based on the most recent recommendations of the French Society of Pediatrics published in 2008, updated from 2003. In summary, breastfeeding is recommended up to 6months. Food diversification can be started between 4 and 6months in children with no allergy risk. Gluten, honey, legumes and cow's milk are introduced between 4 and 7months, after 12months and after 36months, respectively. In atopic children, food diversification is delayed until after 6months and the most allergenic foods (nuts, exotic fruits, peanuts, and shellfish) are introduced after the age of 12months. Eighty-four responses were obtained (51%): 50pediatricians and 34pediatric residents. Sixteen items were classified depending on whether or not an update after 2003 existed. Over 80% of the physicians responded as recommended for the recently updated items for the age of introduction of "solid food in healthy children", "gluten", "cow's milk protein hydrolysates", and "the time until introduction of cow's milk in the atopic child". At best, 65% of physicians responded in accordance with recommendations for items without a recent update, age of introduction of "cow's milk", "milk desserts", "animal proteins", "fats", "vegetables", "use of a hypoallergenic infant formula", and "breastfeeding extension with atopic child". Pediatric residents had the same responses as pediatricians. Seventy-two physicians did not consider the allergenic status of the children to delay the introduction of the most allergenic foods. The lack of complete updating the introduction of solid foods schedule could explain the differences between pediatrician practices and recommendations. Moreover, old recommendations on allergenic food eviction are still available. Pediatricians and pediatric residents partially applied the current recommendations on the introduction of solid food.

Alexithymie, intensité émotionnelle et symptomatologie anxieuse/dépressive : dimensions explicatives du tabagisme

ObjectiveThe objective of this study was to support the existence of emotional dimensions like alexithymia and affective intensity and of psychopathological dimensions like anxiety and depressive symptoms in smoking. We think that smoking could be a manifestation of emotional helplessness. Alexithymia and affective intensity associated with anxiety and depressive symptoms could be a model of emotional functioning which is conducive to smoking. Patients and methodsThe study participants consisted of 222 students (37 males and 185 females; mean age=22.6+5.13 years) from 1st to 5th year of Aix-Marseille University. The sample was divided into two groups: smoking (n=86) and no-smoking (n=136). We administered a protocol to the subjects consisting of three self-assessment scales to assess emotional and psychopathological dimensions. The alexithymia was assessed by the scale of the Twenty-items Toronto Alexithymia Scale (TAS-20). It allows an overall assessment of the level of alexithymia, as well as three dimensions as represented by specific sub scales: difficulty identifying emotions (DIE), difficulty differentiating emotions (DDE) and externally oriented thinking (EOT). The emotional intensity was assessed by the Affective Intensity Measure (AIM). The AIM is a 40-items questionnaire designed to measure the characteristic strength or weakness with which one experiences emotion. The anxiety and depressive symptoms were assessed by Hospital Anxiety and Depression scale (HAD). The HAD is a 14-items scale used to determine the levels of anxiety and depression, seven of the items relate to anxiety and seven relate to depression. These scales have been validated internationally. Statistical analysisWe performed descriptive analysis, correlational analysis (Bravais-Pearson's correlation), linear multiple regression and binary logistic regression model using SPSS.17 software. ResultsThe results showing that smoking subjects are more anxious (M=9.10+3.94; P<0.05) and have more difficulty identifying feelings (M=17.02+5.14; P<0.05) than no-smoking subjects (mean anxiety=7.95+3.58; mean difficulty identifying feelings=15.54+5.25). But smokers are less alexithymics, more specifically in difficulty differentiating emotions (M=12.7+4.73; P<0.001) and externally oriented thinking (M=15.27+3.85; P<0.01) dimensions than no-smokers (mean difficulty differentiating emotions=16+3.89; mean externally oriented thinking=17.22+3.38). The analysis of relationships between the different variables shows the existence of several significant connections. We find a moderate and positive correlation between depression/anxiety and alexithymia (r>25; P<0.01), and a strong positive correlation between depression/anxiety and emotional dimensions of alexithymia: difficulty identifying feelings (r>50; P<0.01). However only with no-smoking subjects, we also find a moderate positive correlation between depression/anxiety and emotional dimensions of alexithymia: differentiating emotions (r>25; P<0.01). In smoker group, the regression analysis shows that only emotional dimensions of alexithymia: difficulty identifying feelings and smoking influence positively and significantly anxious and depressive symptoms (P<0.0001). Anxiety about, the daily consumption of cigarettes (β=0.663) is more discriminating than difficulty identifying feeling (β=0.225). We find the same observation for depression (mean Cig/day: β=0.630; mean difficulty identifying feelings: β=0.201). However, we note in no-smoker group that emotional dimensions of alexithymia: difficulty differentiating emotions also contribute significantly anxiety (B=0.411, P<0.0001). But in any case, alexithymia is more discriminated to emotional intensity. Moreover, the regression analysis shows the daily consumption of cigarettes about, that the terms of symptomatic expression are more discriminating than other variables (mean anxiety: β=0.681; mean depression: β=0.641, P<0.0001). Finally, binary logistic regressions show that anxiety symptoms multiply by 1.5 the probability of smoking. ConclusionsOur study reveals the role of smoking to emotional regulation. The fact that smokers differentiate more easily their emotions could be understood as an attempt to express emotions which cannot be psychical work out. Because, smokers however are more anxious and have more difficult to identify emotions than no-smokers. We think smoking would be an attempt to release psychological suffering through acting. The difficult to identify emotions would be defense against anxiety situation caused by smoking. The study limitations are discussed.

Cell scientist to watch – Emmanuel Boucrot

ABSTRACT Emmanuel Boucrot obtained an undergraduate and a master's degree in biochemistry at the University of Geneva in Switzerland. He pursued his PhD in immunology at the University of Aix-Marseille II in France, supervised by Stéphane Méresse in the laboratory of Jean-Pierre Gorvel. Emmanuel moved to the USA for his postdoctoral training in the laboratory of Tomas Kirchhausen at Harvard Medical School, first as an EMBO fellow and then as a Human Frontiers Science Program fellow. Before starting his own laboratory in 2011, Emmanuel held another postdoctoral position in the laboratory of Harvey McMahon at the MRC Laboratory of Molecular Biology in Cambridge, UK. He is a recipient of a Lister Institute Research Prize and a BBSRC David Phillips Research Fellowship. His group at University College London is interested in studying the mechanisms of clathrin-independent endocytosis, as well as investigating properties of quiescent cells.

On-Line Mass Spectrometry Measurement of Fission Gas Release From Nuclear Fuel Submitted to Thermal Transients

The work presented in this paper has been performed in the framework of a joint research program between Aix-Marseille University and CEA Cadarache. The aim is to develop a mass spectrometer (MS) device for the MERARG facility. MERARG is devoted to the study of fission gas release measurement, from nuclear fuels submitted to annealing tests in high activity laboratory such as LECA-STAR, thanks to gamma spectrometry. The mass spectrometer will then extend the measurement capability from the $\gamma $ -emitting gases to all the gases involved in the release in order to have a better understanding of the fission gas release dynamics from fuel during thermal transients. Furthermore, the mass spectrometer instrument combines the capabilities and performances of both on-line (for release kinetic) and off-line implementations (for delayed accurate analysis of capacities containing total release gas). The paper deals with two main axes: 1) the modelling of gas sampling inlet device and its performance and 2) the preliminary MS qualification/calibration results. The inlet device samples the gas and also adapts the pressure between MERARG sweeping line at 1.2 bar and mass spectrometer chamber at high vacuum. It is a two-stage device comprising a capillary at inlet, an intermediate vacuum chamber, a molecular leak inlet and a two-stage pumping device. Pressure drops, conductance and throughputs are estimated both for mass spectrometer operation and for exhaust gas recovery. The time constant for gas renewal is very low and estimated at about 1 s. Possible gas segregation is also estimated and device modification is proposed to attain a more accurate calibration. Preliminary experimental results obtained from a standard gas bottle show that the quantitative analysis at a few ppm level can be achieved for all isotopes of Xe as well as masses 2 and 4 u.

The performance and the characterization of laser ablation aerosol particle time-of-flight mass spectrometry (LAAP-ToF-MS)

Abstract. Hyphenated laser ablation–mass spectrometry instruments have been recognized as useful analytical tools for the detection and chemical characterization of aerosol particles. Here we describe the performances of a laser ablation aerosol particle time-of-flight mass spectrometer (LAAP-ToF-MS) which was designed for aerodynamic particle sizing using two 405 nm scattering lasers and characterization of the chemical composition of single aerosol particle via ablation/ionization by a 193 nm excimer laser and detection in a bipolar time-of-flight mass spectrometer with a mass resolving power of m/Δm &gt; 600.We describe a laboratory based optimization strategy for the development of an analytical methodology for characterization of atmospheric particles using the LAAP-ToF-MS instrument in combination with a particle generator, a differential mobility analyzer and an optical particle counter. We investigated the influence of particle number concentration, particle size and particle composition on the detection efficiency. The detection efficiency is a product of the scattering efficiency of the laser diodes and the ionization efficiency or hit rate of the excimer laser. The scattering efficiency was found to vary between 0.6 and 1.9 % with an average of 1.1 %; the relative standard deviation (RSD) was 17.0 %. The hit rate exhibited good repeatability with an average value of 63 % and an RSD of 18 %. In addition to laboratory tests, the LAAP-ToF-MS was used to sample ambient air during a period of 6 days at the campus of Aix-Marseille University, situated in the city center of Marseille, France. The optimized LAAP-ToF-MS methodology enables high temporal resolution measurements of the chemical composition of ambient particles, provides new insights into environmental science, and a new investigative tool for atmospheric chemistry and physics, aerosol science and health impact studies.

Geographies of Displacement: Introduction

Back in the summer of 2009 a small group of researchers with a shared interest in the consequences of the spatial turn upon postcolonial studies decided to launch an itinerant seminar that would meet every year once in the spring at Aix-Marseille University, and the following autumn in Montpellier at Paul-Valery University. In subsequent years, the seminar began to attract participants from neighbouring universities in Toulouse, Grenoble and Dijon who, in turn, proposed to organize sessions i...

Congress Report: 20th AEEE Conference and 1st ENSECASS Symposium Aix-Marseille University, 27-29 August 2014: Summary and perspectives

Congress Report: 20th AEEE Conference and 1st ENSECASS Symposium Aix-Marseille University, 27-29 August 2014: Summary and perspectives