LE STUDIUM Multidisciplinary Journal

Manuela Simoni
Elia Paradiso
Véronique Lockhart
Eric Reiter
Livio Casarini
Lucie Pellissier
Pascale Crépieux
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Evidence exists that the gonadotropins LH and FSH can substitute to each other under certain circumstances, in addition to the fact that they can act together in granulosa cells. The aim of this study is to investigate how the two human gonadotropins influence each other in granulosa cells expressing both receptors, or by co-culturing cells expressing either the LHCGR or the FSHR (as a model granulosa/theca interaction). Plasmids encoding the c-myc-tagged-LHCGR and the FLAG-tagged FSHR under the control of an inducible coumermycin-responsive or doxycycline-responsive promoter, respectively were produced. These plasmids were used to permanently transfect human granulosa cell-derived KGN cells and HEK293 cells. The following cell lines were obtained and partially characterized: #1 c-myc-tagged-LHCGR-KGN; #2 FLAG-tagged FSHR_HEK293; #3 FLAG-tagged FSHR-KGN; #4 Double, c-myc-tagged-LHCGR and FLAG-tagged FSHR-KGN. After induction of receptor expression, the cell lines #1 and #2 and #3 responded to hCG and FSH stimulation, respectively by producing cAMP. Receptor expression was demonstrated by RT-PCR and flow cytometry. The characterization of the cell line #4 is ongoing. These cell lines are now available for the study of cell signaling and steroid synthesis, as well as in silico modeling, to gain insight into the dynamics of the intertwined cell response to FSH and LH in granulosa cells. These experiments will continue in parallel in both laboratories involved. Our cell lines represent new, very valuable instruments for the study of molecular pharmacology of FSH and LH, in order to improve infertility treatment, (multi)follicular growth for assisted reproduction, ovulation and spermatogenesis.

Richard Freedman
Philippe Vendrix
David Fiala
Micah Walter
Emilio Sanfilippo
Raffaele Viglianti
Daniel Russo-Batterham
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Building upon recent developments in digital music scholarship, Citations: The Renaissance Imitation Mass investigates similarity and borrowing in music on a massive but detailed scale, using digital tools that only a few years ago were beyond our grasp. Our work focuses on the craft of musical counterpoint, and how musicians of the sixteenth century transformed pre-existing pieces to make intricate cyclic compositions from familiar sounds. The CRIM team, an accomplished group of scholars and data scientists active in Europe, North America, and Australia, will assemble a diverse collaborative network of music scholars and students at colleges, music schools and university graduate programs, extending the reach of digital scholarship to new users, and building new communities.

Bilal Haider Abbasi
Christophe Hano
Nathalie Giglioli-Guivarc’h
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Herbal plants accumulate large amounts of phenolics and pentacyclic triterpenes. The present research project deals with the in vitro culture induction from stem and leaf explants of several medicinal plant species of Centre-Val de Loire under various plant growth regulators (PGRs) for the production of antioxidant and anti-ageing compounds. Among all the tested PGRs, auxins and cytokinins used alone or in combination induced callogenesis in stem/leaf-derived explants. Callus culture displayed feasible total phenolic content and antioxidant activity under optimum hormonal combination. HPLC analysis revealed the presence of plectranthoic acid, oleanolic acid, betulinic acid, caffeic acid and rosmarinic acid. Complete antioxidant and anti-aging potential of extracts with very contrasting phytochemical profiles were investigated. Correlation analyses revealed rosmarinic acid as the main contributor for antioxidant activity and anti-aging hyaluronidase, advance glycation end-products inhibition and SIRT1 activation, whereas, pentacyclic triterpenoids were correlated with elastase, collagenase and tyrosinase inhibition. Altogether, these results clearly evidenced the great valorization potential of herbal plants from CVL for the production of antioxidant and anti-aging bioactive extracts for cosmetic applications.

Igor Lima Maldonado
Christophe Destrieux
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Although cortical elements of the limbic system are quite well defined, the underlying white matter pathways are not well detailed. This project aimed to better describe white matter tracts of the limbic system using both fiber dissection, and in and ex vivo Diffusion Weighted Imaging (DWI) techniques. In vivo data (from DWI and neuropsychological evaluations) were obtained from healthy subjects aged 82 and over previously enrolled in the FIBRATLAS project funded by the French Research Agency and run in the host laboratory. Correlations between neuropsychological and white matter characteristics on DWI were examined in this group to infer function of the limbic white matter tracts. Ex vivo data from the FIBRATLAS project database and from the Tours Body Donation Program were examined. The brains were extracted and used to study the anatomy of the limbic white matter tracts employing both DWI and fiber dissection according to a variant of the Klingler’s method.

Guoxian Chen
Magali Ribot
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We design a scheme for the Euler equations under gravitational fields based on our subcell hydrostatic reconstruction framework.

To give a proper definition of the nonconservative product terms due to the gravitational potential, we first separate the singularity to be an infinitely thin layer, on where  the potential is smoothed  by defining an intermediate potential without disturbing its monotonicity ; then the physical variables are extended and controlled to be consistent with the Rayleigh-Taylor stability, which contribute the positivity-preserving property to keep the nonnegativity of both gas density and pressure even with vacuum states. By using the hydrostatic equilibrium state variables the well-balanced property is obtained to maintain the steady state even with vacuum fronts.  In addition, we proved the full discrete discrete entropy inequality, which preserve the convergence of the solution to the physical solution, with an error term which tends to zero as the mesh size approaches to zero if the potential is Lipschitz continuous. The new scheme is very natural to understand and easy to implement.

The numerical experiments demonstrate the scheme's robustness to resolve the nonlinear waves and vacuum fronts.

Marcelo Gustavo Lorenzo
Claudio R. Lazzari
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Insects vectoring human disease, like mosquitoes and kissing-bugs, endure a high risk of predation related to their life histories. Therefore, insect vectors are expected to have a finely adapted behavioral repertoire to survive in the context of their close association to vertebrate hosts. The study of molecular bases of their perception of the environment and their behavior, is relevant to understand the evolution of hematophagy as well as to promote the discovery of new targets of opportunity for developing rational control methods. Our long-lasting scientific collaboration has been dedicated to these tasks and the support of the Le Studium Foundation has been instrumental to further promote its development. We report here a series of studies that have been completed during the stay in the region Centre. Kissing-bugs are nocturnal insects that spend daylight hours hidden inside narrow shelters. Therefore, comprehending shelter choice, as well as the cues that trigger foraging decisions seems essential in order to predict bug distribution and activity precisely. We have focussed on Rhodnius prolixus, one of the two main vectors of Chagas disease in the Americas, and the way they use shelters. As an outcome of these investigations, three scientific papers have been published to report factors affecting shelter choice by bugs, the lack of a chemical marking system in bugs of this genus and the key role that host odours play in promoting bug foraging outside shelters. In parallel, we have described what seem to be diverging locomotory profiles in these bugs suggesting that foraging strategies can vary from “sitter” to “rover” individuals. As a third topic, we have developed a synthetic blend of compounds imitating the effects of the sexual pheromone attracting males to R. prolixus females. In a fourth topic we have uncovered what appears to be a local modulatory system present in the antennae of insects including the synthesis of transcripts for neuropeptides, GPCRs and nuclear receptors. Finally, we have revised the molecular bases of sensory processes in triatomine bugs vectors of Chagas disease in a review publication.

Satyajit Phadke
Erwan Coadou
Julie Pires
Alexander Korzhenko
Mérièm Anouti
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The sulphur electrode in LiS batteries suffers from rapid capacity loss and low efficiency due to the solubility of long chain polysulphides formed during discharge. Herein, we demonstrate the beneficial effect of original catholyte formulations containing redox active organyl disulphides (PhS2Ph) on the capacity utilization and retention as well as the efficiency in LiS batteries. Resulting from the chemical equilibria in the electrolyte between the sulphur/polysulphides (S8/Sx2-) and disulphide/thiolates (PhS2Ph/PhSx-), the polysulphide redox shuttle phenomenon is minimized due to the suppression of formation of soluble polysulphides (Sx2-, x > 4). Using the catholyte containing 0.4 M Ph2S2 as an additive in a standard base electrolyte (DOL/DME + LiTFSI/LiNO3), a stable capacity of 1050 mAh.g-1 is obtained under galvanostatic cycling at C/5 with a coulombic efficiency of >99.5%. At 45°C, it is shown that the formulated catholyte enables galvanostatic cycling at a high c-rate of 1C over 500 cycles with a capacity above 900 mAh.g-1 and a high energy efficiency of 82%.

Agnieszka Synowiec
Christophe Hano
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During this fellowship I performed several greenhouse and laboratory experiments, aiming at assessing the phytotoxic and microbiological effects of microencapsulated peppermint (Mentha x piperita L.) essential oil (MPO). The different doses of MPO were applied in the pot experiments either into vermiculite or top layer of arable soils. As the acceptor-species, I used four maize cultivars, one cultivar of mustard and a weed– lambsquarters (Chenopodium album L.). The microbiological analyses were performed using i) commercial strain of arbuscular fungus Rhizophagus irregularis on maize roots by intersection method, and ii) natural soil-microbiota by FDA biotest. I have found, based on the ED50 analysis, that the phytotoxic effect of MPO is both dose and species as well as soil-medium dependent. The biochemical analyses revealed, that the plants’ response to the application of MPO is typical for the allelopathic stress. The microbiological responses to the MPO applications were not clear enough to conclude and should be continued further.

Carmen Díaz Orozco
Brigitte Natanson
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In agreement with the research project proposed to Le Studium, our work consisted in the development of the following aspects: 1. - Tracking and compilation of biblio-hemerographic materials at the BNF; 2. - Selection and analysis of Juana Manso's corpus of materials; 3. - Organization of two scientific events; 4. - Attendance, as speaker, at a scientific event; 5.- Writing of two book chapters; 6. - Organization of the volume Forjar miradas. Imagen y cultura visual en la América latina del siglo XIX. Iberoamericana Vervuert (in progress) and, 7. - At the request of the Scientific Relations Manager of Le Studium, design of the research proposal "Regarder au XIXe. Panoptisme et culture visuelle.”.

Temenuga Trifonova
Raphaële Bertho
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The increased mobility of large groups of people from outside and inside Europe has influenced the socio-geographical fixity of a continent of nation-states, putting in question both the concepts of ‘national identity’ and ‘European identity’. This book project considers contemporary debates around the idea of ‘Europe’ and ‘European identity’ through an examination of recent European films dealing with various aspects of globalization (the refugee crisis, labor migration, the resurgence of nationalism and ethnic violence, international tourism, neoliberalism, post-colonialism etc.) in order to reflect on the ambiguities and contradictory aspects of the figure of the migrant and the ways in which this figure challenges us to rethink core concepts such as European identity, European citizenship, justice, ethics, liberty, tolerance, and hospitality in the post-national context of ephemerality, volatility, and contingency that finds people desperately looking for firmer markers of identity. By drawing attention to the structural and affective affinities between the experience of migrants and non-migrants, Europeans and non-Europeans, the book argues that it is becoming increasingly difficult to separate stories about migration from stories about life under neoliberalism in general.