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La liberté d'expression du professionnel dans la communication d'informations aux consommateurs et aux autres professionnels
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Comparative Structural and Biophysical Investigation of Lycosa erythrognatha Toxin I (LyeTx I) and Its Analog LyeTx I-b
No full textInternational audienceBackground/Objectives: This study investigates the structural and biophysical properties of the wild-type antimicrobial peptide LyeTx I, isolated from the venom of the spider Lycosa erythrognatha, and its analog LyeTx I-b, designed to enhance antibacterial activity, selectivity, and membrane interactions by the acetylation and increased amphipathicty. Methods: To understand the mechanisms behind these enhanced properties, comparative analyses of the structural, topological, biophysical, and thermodynamic aspects of the interactions between each peptide and phospholipid bilayers were evaluated. Both peptides were isotopically labeled with 2 H 3 -Ala and 15 N-Leu to facilitate structural studies via NMR spectroscopy. Results: Circular dichroism and solid-state NMR analyses revealed that, while both peptides adopt α-helical conformations in membrane mimetic environments, LyeTx I-b exhibits a more amphipathic and extended helical structure, which correlates with its enhanced membrane interaction. The thermodynamic properties of the peptide-membrane interactions were quantitatively evaluated in the presence of phospholipid bilayers using ITC and DSC, highlighting a greater propensity of LyeTx I-b to disrupt lipid vesicles. Calcein release studies reveal that both peptides cause vesicle disruption, although DLS measurements indicate distinct effects on phospholipid vesicle organization. While LyeTx I-b permeabilizes anionic membrane retaining the vesicle integrity, LyeTx I promotes significant vesicle agglutination. Furthermore, DSC and calcein release assays indicate that LyeTx I-b exhibits significantly lower cytotoxicity toward eukaryotic membranes compared to LyeTx I, suggesting greater selectivity for bacterial membranes. Conclusions: Our findings provide insights into the structural and functional modifications that enhance the antimicrobial and therapeutic potential of LyeTx I-b, offering valuable guidance for the design of novel peptides targeting resistant bacterial infections and cancer
Influence of DIC settings on temperature fields in combined thermal-kinematic measurements for heterogeneous tests
No full textInternational audienceAbstract. The integration of Digital Image Correlation with Infrared Thermography (DIC-IRT) in heterogeneous tests provides information rich kinematic and thermal field data. Thanks to the commercial availability of optical devices, this technique is gaining attraction to characterize the thermomechanical behavior of metals. However, achieving accurate full-field results requires a deep understanding of all the uncertainties arising from the complex measurement and post-processing chains. To this end, this paper studies the previously unexplored effect of user-dependent DIC settings on temperature fields. The solution approach relies on a Digital Virtual Twin (DVT) simulating a post-necking tensile test on a thick S700MC steel assisted with DIC-IRT. The novelty here is that the DVT combines the state-of-the-art virtual image deformation with the metrological aspect of thermal measurement. The results show that, under heterogeneous temperature and strain fields, DIC settings introduce a systematic temperature error with local biases comparable to the measurement error. According to this finding, a spatially converged displacement field is required to measure an accurate thermal field in heterogeneous tests
Le nomadisme numérique comme composante des tracances : Exploration des pratiques professionnelles mobiles
No full textInternational audienceThe portability of information and communication technologies has led to major changes in the world of work since the late 20th century. Whether employees, entrepreneurs, or freelancers, many workers are freeing themselves from geographic constraints and seizing new opportunities to become more mobile and to carry out their professional activities in amenity-rich locations.This paper examines two phenomena often conflated by the media, public authorities, and civil society at large: digital nomadism and "workations" (a portmanteau of "work" and "vacation"). We hypothesize that digital nomadism is a specific form of workation. Digital nomadism refers more broadly to a lifestyle in which individuals rely primarily on mobile devices for work and leisure, enabling them to remain connected while on the move. Workations, on the other hand, involve working remotely from a vacation-like setting, blending work time with leisure.Drawing on interview-based surveys with these so-called "geo-independent" workers, we highlight the diversity of situations in which individuals experience workations—such as working from a second home, staying in hotels or coliving spaces, attending retreats, and … practicing digital nomadism. In other words, our aim is to situate digital nomadism within a broader spectrum of mobile professional practices.La portabilité des technologies de l’information et de communication a entrainé depuis la fin du XXe siècle des changements majeurs le monde du travail. Qu’ils soient salariés, entrepreneurs ou indépendants, bons nombres de travailleurs s’affranchissent des contraintes de localisation et profitent de ces nouvelles opportunités pour devenir plus mobiles et investir de nouveaux territoires à fortes aménités pour exercer leur activité professionnelle.Cette communication examine deux phénomènes souvent amalgamés par les médias, les acteurs publics et la société civile en général : le nomadisme numérique (NN) et les tracances (contraction de "travail" et "vacances", ou "workations" en anglais). Nous posons l’hypothèse que le NN constitue une modalité spécifique des tracances. Le NN désigne davantage un mode de vie où les individus utilisent principalement des appareils mobiles pour le travail et les loisirs, leur permettant de rester connectés lors de leurs déplacements. Les tracances font quant à elles référence à la pratique consistant à travailler à distance depuis un lieu de villégiature, combinant ainsi journées et temps de travail et de détente.En nous appuyant sur les résultats d’enquêtes par entretiens menés auprès de ces travailleurs « géo-indépendants », nous montrons qu’il existe une diversité de situations menant ces individus à vivre des situations de tracances comme le travail en résidence secondaire, les séjours mixtes en hôtel et espace de coliving, les retraites et … le nomadisme numérique. En d’autres termes, notre objectif consiste à resituer cette dernière pratique parmi d’autres
A Case Report on Multiple Renal Infarctions in Spontaneous Double Renal Artery Dissection
No full textInternational audienceAim: This study reports a rare clinical case of spontaneous renal artery dissection (SRAD) presenting with multiple renal infarctions.Background: As spontaneous renal artery dissection (SRAD) is a rare cause of abdominal pain, bilateral dissection is an extremely rare event. It can be defined as a dissection of the renal artery with no underlying vascular disease, renal artery intervention, or trauma. Only approximately two hundred cases of SRAD have been reported in the literature. The diagnosis is often delayed due to the rarity of the disease and non-specific clinical presentations such as flank pain, hypertension, fever, nausea, vomiting, and hematuria, which can be often misdiagnosed as a genito-urinary infection or gastrointestinal or bowel disease. Before 1980, the diagnosis of SRAD was mostly confirmed via autopsy or, rarely, via angiography. At present, the diagnosis is made using advanced imaging approaches, including computed tomography angiography (CTA) and magnetic resonance angiography (MRA), with a higher number of incidentally diagnosed SRADs.Methods: The case of a 49-year-old man who was referred to our Emergency Room with acute abdominal flank lower back pain, uncontrolled hypertension, headache, and malaise has been reported. Laboratory tests and radiological examinations (computed abdominal tomography and multiplanar reconstruction) have been performed that revealed multiple infarctions and ischemic areas with hypoperfusion in the upper middle third of the left kidney and in a large part of middle and lower areas of the right kidney; the left renal artery exhibited increased intimal thickening and arteritis.Results: The multiplanar reconstruction revealed bilateral renal artery dissection and multiple arterial infarctions disseminated throughout both kidneys. After a clinical follow-up and hypertension retargeting, the patient was discharged with dual antiplatelet therapy and ACE inhibitor drugs. No lipid-lowering therapy was needed.Conclusions: SRAD remains a diagnostic challenge as it could be misdiagnosed or receive a delayed diagnosis due to its relative rarity and non-specific presentation. The gold standard is enhanced computed tomography (CT) scans, and if the diagnosis is positive, vascular multiplanar reconstruction is generally suggested, as it can display lesions more clearly. However, to date, a consensus has not been reached on the most appropriate treatment. Conservative therapy, open surgery, and intravascular intervention have been reported as treatments for SRAD. Additionally, stabilizing blood pressure must be the primary objective not only during hospitalization but also at discharge when planning clinical and radiological follow-ups for cases that do not require urgent endovascular or open surgery treatment but could worsen or relapse
La trajectoire singulière d'une feuille de maïs
No full textInternational audience« La trajectoire singulière d'une feuille de maïs » est un film réalisé à partir d'une enquête de Francesca Cozzolino sur la réalisation d'objets de design issus de la culture de maïs dans l'État de Puebla, au Mexique. Le film permet à la chercheuse de présenter son terrain et les données produites dans le cadre de cette enquête ethnographique qui prend la forme d'une narration visuelle associant un contexte local (la disparition du maïs natif de la région semi-aride de Mixteca au Mexique) à un événement de l'histoire contemporaine globale (les accords de libre-échange ALENA). Par le biais d'une voix off - la voix des épis de maïs natif - l'anthropologue raconte comment le designer mexicain, Fernando Laposse en recherche d'une approche durable et locale du design ainsi que d'un moyen pour soutenir une communauté paysanne en difficulté, réussit à convaincre un groupe de familles du petit village de Tonahuixtla de l'état de Puebla à travailler la terre en suivant des principes proches de la permaculture (milpa) et à ensuite prendre en charge la transformation des feuilles de maïs cultivées en suivant des procédés semi mécaniques, de façon à obtenir un matériau de revêtement élégant : le Totomoxtle. La voix off, soutenue par le montage et des procédés d'animation 2D, s'appuie donc sur les documents photographiques, vidéo et sonores de la chercheuse, ainsi que sur la création d'images animées pour donner à comprendre la démarche du designer et les enjeux écologiques que ce cas pose à une plus large échelle. Construit à trois voix, ce film associe une anthropologue, une réalisatrice de films documentaire spécialisée dans la documentation des activités professionnelles collectives dans les sciences, Coralie Maurin, et d'une designer graphique, Juliette Nier, qui travaille notamment avec les outils de l'animation 2D autour et des phénomènes en confrontation avec des réalités difficiles à appréhender, parfois incongrues ou complexes à expliquer. Le film explore les codes de la fiction, du documentaire et de l'animation pour dévoiler au spectateur un projet se situant aux limites de la tradition inventée et de l'innovation technique. Dans une perspective plus large, le cas de Totomoxtle conduit à penser la question de la conception et de la transmission d'une technique, dans un contexte où s'entrechoquent les subtiles hybridations culturelles, économiques, politiques et écologiques, qui caractérisent nos mondes contemporains
Mareare in mari, edere in castro. Approvisionnement et consommation des animaux marins dans les résidences élitaires d’Aquitaine au Moyen Âge (Xe–XVe siècle)
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A Large-Scale Optimization Framework for Simultaneous Design and Routing of Wind-Assisted Ships
No full textInternational audienceThis paper presents a comprehensive approach to optimizing the performance of wind-assisted ships. The proposed optimization framework simultaneously addresses ship routing and design, considering the complex interactions between design parameters and route optimization across multiple weather scenarios. Optimal control methods, including the direct multiple shooting technique and automatic differentiation, are employed to efficiently optimize both routing and design parameters, resulting in a large-scale optimization problem. The methodology is demonstrated through a case study of a 2200-TEU container ship equipped with Flettner rotors, operating on a transatlantic route between Brittany and Halifax. The results provide an objective estimate of fuel savings, highlighting the importance of integrated optimization for wind-assisted propulsion systems, while maintaining computational efficiency suitable for iterative design processes. Compared to conventional methods, this approach drastically reduces optimization times, enabling rapid design iterations and informed decision-making. Furthermore, the study offers insights into the sensitivity of fuel consumption to key design parameters, such as the number and placement of Flettner rotors, providing a more accurate and comprehensive estimate of potential energy savings compared to conventional methods. By overcoming the limitations of traditional polar-diagram-based methods, this framework provides a more accurate and dynamic assessment of wind-assisted propulsion systems. These findings emphasize the necessity of integrated optimization for maximizing performance and sustainability in maritime transport
Modélisation du thermoformage de structures en composites tubulaires, et de ses conséquences sur ses propriétés en service
No full textInternational audienceModélisation du thermoformage de structures en composites tubulaires, et de ses conséquences sur ses propriétés en servic