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New insights into oral preparation before radiotherapy affecting the oral cavity
No full textInternational audiencePurposeRadiotherapy, when it affects the oral cavity, can cause various side-effects and may even lead to more severe complications such as osteoradionecrosis. The development in radiotherapy and dental care techniques, has enabled the optimization of oral management before radiotherapy, enhancing treatment outcomes and reducing side effects. This research focuses on the latest advances in oral health and dental rehabilitation in the context of radiation therapy, comparing them to historical recommendations and discussing their indications.Material and methodsA bibliographic search using the search engine PubMed, between 2009 and 2024, was carried out to evaluate the evolution of oral conditioning and dental rehabilitation in the context of radiotherapy.ResultsA total of 215 references were retrieved (first 155 references, then 60 more added secondarily). Recommendations have changed over time, prioritizing a more conservative stance aimed at preserving oral functionality and preventing the nutritional and psychological deficits secondary to edentulism. The development of new materials and strategies in dental care and implantology and the evolution of radiotherapy techniques and software, have made it possible to optimize oral management before radiotherapy and to create, for the first time, a personalized and precise ‘dossier’, which may change the way in which planning before radiotherapy and the patient's quality of life are considered.ConclusionNew practices, techniques and recommendations have emerged in the last decade to reduce radiation morbidity and improve rehabilitation
Victor Barabino , Des guerriers d’Odin aux chevaliers du Christ : la relation combattant/divinité au prisme de la christianisation dans la diaspora scandinave médiévale, IXe-XIVe siècle, thèse soutenue le 2 décembre 2023 à l’université de Caen Normandie, 816 p.
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Dynamique de déformation d'un réservoir de liquide servant à la stabilisation d'une structure flottante en mouvement complexe
No full textThe sloshing is a phenomenon appears inside partially filled tanks, it refers to the oscillatory movement of the free surface of the liquid. When these tanks are carried by floating systems, used for their stabilization, the sloshing becomes more complex. The objective of this thesis is to model the dynamics of liquid sloshing in floating tanks with a deformable wall into IFS, under pitch and heave motion. An experimental scheme has been implemented to build up an experimental database. The device is designed to study and analyze the sloshing under the effets of pitch motion. The obtained results were exploited to validate a numerical model developed. The numerical model is implemented taking into account the FSI effects. A partitioned coupling is used and the evolution of the free surface is treated by the VOF method. This model is validated in the case of the horizontal harmonic excitation, and in the case of a pitch excitation. The model is then applied to studying sloshing in a partially filled deformable tank, once subjected to garvitational effects and another subject to pitch and heave motions.Le ballottement est un phénomène qui apparaît à l’intérieur des réservoirs partiellement remplis, il désigne le mouvement oscillatoire de la surface libre du liquide. Lorsque ces réservoirs sont portés par des systèmes flottants, servant à leurs stabilisations, le ballottement devient de plus en plus complexe. L’objectif de cette thèse est de modéliser la dynamique de ballottement des liquides dans des réservoirs flottants à parois déformables en IFS, sous une excitation de tangage ou de roulis. Un dispositif expérimental a été mis en œuvre afin de constituer une base de données expérimentales. Ce dispositif a pour objet d'étudier et d'analyser le ballottement sous l’effet de mouvement de tangage. Les résultats obtenus ont été exploités pour valider un modèle numérique. Celui-ci est mis en place en prenant en compte les effets de l’IFS. Un couplage partitionné est utilisé et l’évolution de la surface libre est traité par la méthode VOF. Ce modèle est validé dans le cas d’une excitation harmonique horizontale, et dans le cas d’une excitation de tangage. Le modèle est ensuite appliqué à l’étude de ballottement dans un réservoir déformable partiellement rempli, soumis aux effets gravitationnels et aux effets d'accélération des mouvements de tangage et de pilonnement
The Matrix Subcode Equivalence problem and its application to signature with MPC-in-the-Head
No full textNowadays, equivalence problems are widely used in cryptography, most notably to establish cryptosystems such as digital signatures, with MEDS, LESS, PERK as the most recent ones. However, in the context of matrix codes, only the code equivalence problem has been studied, while the subcode equivalence is well-defined in the Hamming metric. In this work, we introduce two new problems: the Matrix Subcode Equivalence Problem and the Matrix Code Permuted Kernel Problem, to which we apply the MPCitH paradigm to build a signature scheme. These new problems, closely related to the Matrix Code Equivalence problem, ask to find an isometry given a code and a subcode . Furthermore, we prove that the Matrix Subcode Equivalence problem reduces to the Hamming Subcode Equivalence problem, which is known to be NP-Complete, thus introducing the matrix code version of the Permuted Kernel Problem. We also adapt the combinatorial and algebraic algorithms for the Matrix Code Equivalence problem to the subcode case, and we analyze their complexities. We find with this analysis that the algorithms perform much worse than in the code equivalence case, which is the same as what happens in the Hamming metric. Finally, our analysis of the attacks allows us to take parameters much smaller than in the Matrix Code Equivalence case. Coupled with the effectiveness of \textit{Threshold-Computation-in-the-Head} or \textit{VOLE-in-the-Head}, we obtain a signature size of 4 800 Bytes, with a public key of 275 Bytes. We thus obtain a reasonable signature size, which brings diversity in the landscape of post-quantum signature schemes, by relying on a new hard problem. In particular, this new signature scheme performs better than SPHINCS+, with a smaller size of public key + signature. Our signature compares also well with other signature schemes: compared to MEDS, the signature is smaller, and we reduced the size of the sum of signature and public key by a factor close to 5. We also obtain a signature size that is almost half the size of the CROSS signature scheme
La question du risque dans la région de Dakar : diagnostic territorial par une approche multirisque
No full textDakar is a coastal city located on the Cape Verde peninsula, which juts out into the Atlantic Ocean. The capital of Senegal, Dakar occupies 0.28% (around 550 km2) of the country's surface area, but is home to 22% of the population and produces around 46% of the country's wealth, concentrating almost 90% of the country's industrial activity. In addition to the natural hazards specific to the area, land-use planning choices have resulted in the superimposition of a multi-risk area. As a result, Dakar today has close proximity between residential and productive areas. In this research, we consider that there is a link between risks in the Dakar region and land-use planning. We consider that the current situation is the product of shortcomings in land-use planning at both regional and national levels. To spatialize hazards and characterize vulnerability, we applied several methods ranging from GIS modeling to the use of vulnerability indices combining spatial data, index calculations and information aggregation. The results confirm our initial hypothesis, namely that the risk situation in Dakar is inextricably linked to the development of the Senegalese territory. In addition, we noted that flooding remains the main source of concern for the majority of respondents, due to its almost annual recurrence in several sectors of the capital. Industrial risk, thought to be underestimated or even ignored by the people of Dakar, is well taken into account, but does not arouse any particular fears due to its abstract nature.Ville littorale, Dakar est située sur la presqu'île du Cap-Vert, une péninsule qui s'avance dans l'océan Atlantique. Capitale du Sénégal, Dakar occupe 0,28 % (environ 550 km2) soit une minuscule partie de la superficie nationale, mais concentre 22 % de la population, et produit environ 46 % de la richesse nationale en concentrant notamment près de 90% de l’activité industrielle du pays. Aux risques naturels propres au milieu, les choix en matière d’aménagement du territoire ont fini par superposer un espace multirisque. C’est ainsi que Dakar présente aujourd’hui une proximité étroite entre zones résidentielles et zones à vocation productive. Dans cette recherche, nous considérons qu’il existe un lien entre les risques dans la région de Dakar et l’aménagement du territoire. Nous considérons que la situation actuelle est le produit de carences en matière d’aménagement du territoire à la fois à l’échelle de la région et aussi à l’échelle nationale. Pour spatialiser les aléas et caractériser la vulnérabilité, nous avons appliqué plusieurs méthodes allant de la modélisation sur SIG à l’utilisation d’indices de vulnérabilité mêlant données spatiales, calculs d’indices et agrégation d’informations. Les résultats obtenus nous confortent sur notre problématique de départ à savoir que la situation des risques sur le territoire de Dakar est indissociable de l’aménagement du territoire sénégalais. En outre, nous avons noté que le risque d’inondation reste aux yeux de la majorité des personnes interrogées la principale source de préoccupations à cause de sa récurrence quasi annuelle dans plusieurs secteurs de la capitale. Le risque industriel qu’on pensait sous-estimer voire ignorer par les dakarois est bien pris en compte sans pour autant susciter de craintes particulières du fait de son caractère abstrait
Does the European low-carbon policy impact price uncertainty in fossil energy markets?
No full textInternational audienceThis paper aims to assess the potential effects of a low-carbon policy on price uncertainty in fossil energy markets. For this purpose, we propose text-as-data methods that rely on unsupervised machine-learning algorithms applied to European Union (EU) laws and newspapers. These methods are used to construct two monthly indices over the reference period 1997-2021: (i) a news-based index that reflects uncertainty about the regulatory framework of low-carbon policy as relayed in the press, and (ii) a law-based index that reflects structural changes in European low-carbon policy. Given the support for the carbon phase-out policy, we further examine the extent to which each index relates to price uncertainty dynamics in fossil energy markets. As a result, we find that an increase in the news-based index leads to a positive short-run effect on price uncertainty. Similarly, we observe both dampening short-run and persistent effects of the law-based index on price uncertainty. Thus, stabilizing price uncertainty dynamics through regulations serves as a measure of the efficacy and resilience of European low-carbon policy. This result is robust to the consideration of macroeconomic factors
La dame derrière les camélias : Μarie Duplessis, matière à une réflexion sociale, mythique et littéraire
No full textThanks to research carried out in previous years on the status of women, the history of prostitution and that of the courtesan Marie Duplessis, it is now possible to take a closer look at the real-life character who has become a literary and artistic myth. And it's this myth that we'll be focusing on to show how Marguerite Gautier's modernity has made her a subject taken up and reinterpreted by contemporary and later artists: in the 1950s, she inspired Roberto Gavaldón's film Camelia in Mexico City, where the economic and cultural growth of post-war Mexican society mirrored the wealth of July Monarchy France, and Maria Felix appeared as the epitome of feminine elegance, following in the footsteps of Marie Duplessis ; in the 1990s, as America recovers from a harsh recession, a new Gilded Age is represented in Pretty Woman through the figure of wealthy entrepreneur Edward (Richard Gere) who meets Vivian (Julia Roberts), a prostitute with a heart of gold, who breathes new life into the legend of Marguerite Gautier ; In 2001, Baz Luhrmann transforms her into Satine in the flamboyant setting of Moulin Rouge; finally, in 2018, Camille Vidal-Naquet reinterprets her as a young Parisian escort boy with tuberculosis in Sauvage, to denounce, as Dumas fils did before, a situation of misery and abandonment that has changed little since her time. Through music, La Traviata has made La Dame aux camélias a universal phenomenon: in 2018, in Jung Ku-ho's staging, she became a Kisaeng (Korean courtesan) and Armand a young yangban (educated, noble man) from the Joseon dynasty (one of the most prosperous); Violetta wears luxurious hanbok (traditional dresses) in a minimalist setting inspired by Korean art; in 2019, Simon Stone's vulgar Traviata turns Violetta into an “influencer” who exchanges Whatsapp messages with Alfredo, sitting in a kebab fast-food restaurant...Dumas fils's legacy in Marguerite Gautier and Verdi's in Violetta are particularly widespread. My thesis is based not only on an analysis of the novel, the play and the opera, but also on the way in which this “Cinderella with princes, not all of them charming” has continued to influence modern society right up to the present day: directors, actresses and spectators continue to reinterpret, react to (or recognize themselves in) this woman covered in camellias and mystery.Grâce aux recherches effectuées au cours des précédentes années sur la condition de la femme, l’histoire de la prostitution et celle de la courtisane Marie Duplessis, il est possible d’approcher de plus près le personnage réel qui est devenu un mythe littéraire et artistique. Et c’est sur ce mythe que l’effort sera porté pour montrer comment Marguerite Gautier est devenue, grâce à sa modernité, un sujet repris et réinterprété par les artistes contemporains et postérieurs : dans les années 1950, elle inspire à Mexico le film Camelia de Roberto Gavaldón, la croissance économique et culturelle de la société mexicaine après-guerre reflétant tel un miroir la richesse de la France de la Monarchie de Juillet et Maria Felix apparaissant comme l’épitomé de l’élégance féminine, à l’instar de Marie Duplessis ; dans les années 1990, alors que l’Amérique récupère d’une dure récession, un nouveau Gilded Age est représenté dans Pretty Woman à travers la figure du riche entrepreneur Edward (Richard Gere) qui rencontre Vivian (Julia Roberts), prostituée au cœur d’or, qui donne un nouveau souffle à la légende de Marguerite Gautier ; Baz Luhrmann en 2001 la transforme en Satine dans le décor flamboyant de Moulin Rouge ; finalement, en 2018, Camille Vidal-Naquet la réinterprète en jeune escort boy parisien et tuberculeux dans Sauvage, pour dénoncer comme Dumas fils auparavant, une situation de misère et d’abandon qui a peu changé depuis son époque. Dépassant à travers la musique les barrières de la langue et de la culture, La Traviata a fait de La Dame aux camélias un phénomène universel : en 2018, dans la mise en scène de Jung Ku-ho, elle est devenue une Kisaeng (courtisane coréenne) et Armand un jeune yangban (homme éduqué et noble) de la dynastie Joseon (une des plus prospères) ; Violetta y porte de luxueuses hanbok (robes traditionnelles) dans un décor minimaliste inspiré de l’art coréen ; en 2019, la vulgaire Traviata de Simon Stone fait de Violetta une « influenceuse » qui échange des messages Whatsapp avec Alfredo, assise dans un fast-food de kebabs… L’héritage de Dumas fils à travers Marguerite Gautier et celui de Verdi avec Violetta est particulièrement répandu. Mon travail de thèse repose non seulement sur l’analyse du roman, de la pièce, de l’opéra, mais aussi sur la façon dont cette « Cendrillon avec des princes, pas tous charmants » a continué à influencer la société moderne jusqu’à nos jours : metteurs en scène et réalisateurs, actrices et spectateurs continuent de réinterpréter, réagir à (ou se reconnaitre dans) cette femme couverte de camélias et de mystère
Advocacy by nonprofit scientific institutions needs to be evidence-based: a case study
No full textInternational audienceScientific institutions, including universities and research centers, occasionally engage in advocacy to gain financial support. However, this can be problematic if they selectively present scientific evidence. We describe a case involving a French semi-public foundation dedicated to clinical research on four adult psychiatric disorders: autism without intellectual disability, treatment-resistant depression, schizophrenia, and bipolar disorder. The foundation has claimed that an initial assessment at any of its Expert Centers led to a 50 % reduction in hospitalization days. We analyzed communication directed at the public in the French press, advocacy efforts towards members of the French Parliament (MFPs), evidence supporting this claim within those activities, and MFPs' initiatives that addressed the foundation's request. However, the reduction in hospitalization originated from a single study of bipolar disorder patients, which lacked a control group and had other methodological flaws. No scientific publications supported similar claims for the other three disorders. On May 2, 2024, 70 members of the French Parliament introduced a bill aimed at integrating these Expert Centers into the healthcare system. Justifications for the bill explicitly cited the 50 % reduction in hospitalization for all four conditions. This case highlights the need for policy makers and journalists to verify the robustness of scientific claims before these become policy. It also emphasizes the responsibility of scientists and journal editors to recognize and mitigate spin in research studies and opinion articles and to develop tools that help evaluate advocacy and lobbying claims in scientific contexts
siRNA Interaction and Transfection Properties of Polycationic Phosphorus Dendrimers
No full textInternational audienceGlioblastoma multiforme (GBM) is the most common type of primary brain tumor in adults and has a poor prognosis. Small interfering RNA (siRNA) can disrupt different mechanisms involved in the genesis of several diseases including GBM. However, siRNA complexation with nonviral cationic carriers is required to transport siRNAs inside cells and promote its function. We have designed and synthesized new cationic phosphorus dendrimers bearing either 6, 12, or 24 pyrrolidinium or piperidinium groups on their surface. These dendrimers bound siRNA, those bearing terminal pyrrolidinium having the highest affinity. However, they showed marked differences in protecting siRNA from RNase-mediated degradation. Molecular modeling suggested that, beyond the overall protonation status, the intrinsic flexibility and individual binding properties of these dendrimers contributed to the modulation of biological profiles. However, these phosphorus dendrimers were unable to transport significant amounts of siRNA into GBM cells and, accordingly, transfection was inefficient