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Victimhood, Agency, and Vulnerability: Portraits of Delhi Manual Workers in Aman Sethi’s A Free Man (2011) and Mridula Koshy’s Bicycle Dreaming (2016)
No full textInternational audienceThis chapter examines the representation of Delhi manual workers in Aman Sethi's literary reportage A Free Man (2011), about homeless daily construction workers in an Old Delhi labour market, and Mridula Koshy's novel Bicycle Dreaming (2016), which portrays the children of an itinerant buyer of waste and a scavenger in South Delhi. The two books feature disenfranchized people or characters from the Indian working class, who may be seen as the victims of a social and economic system which feeds on the vulnerability of manual workers in deprived areas. However, I will show that Koshy's novel and Sethi's reportage blur the lines between victimhood and agency, refusing to make their books narratives of either abjectivity or aspiration. I will also question whether empathy is the appropriate response to such books and explore the distribution of vulnerability which may pertain not only to the manual workers but also, partly, to authors and readers.</div
Internal Flow Structure in Rotating Detonation Engines with Non-Constant-Area Channels
No full textInternational audienceA rotating detonation engine (RDE) featuring two fixed channel geometries, with angles -3deg (converging) and 5deg (diverging), was investigated experimentally. Optical observations, pressure measurements, and thrust measurements during gaseous H2-O2 combustion tests were conducted to investigate the effects of axial flow speed on detonation waves and the acceleration process of the internal flow. The results were compared with C2H4-O2 combustion data to assess how heating value affects the internal flow. An acrylic wall was used to capture the side view of the internal flow, and a stainless-steel wall equipped with eight or nine pressure ports in the axial direction measured pressure. Combustion tests were performed under both low-back-pressure and atmospheric conditions. Strong circumferentially propagating OH* luminosity and a broadband chemiluminescence area were observed from the side of the RDE. A high-luminescence area propagating downstream of the main combustion region was inclined backward or forward relative to the direction of propagation, depending on the channel’s angle. The time-averaged pressure distribution suggested that the internal flow accelerated to critical speed in the middle of the engine within the diverging channel and near the exit in the converging channel, indicating distinct acceleration mechanisms depending on the channel angle
<i>“I’ve always felt in the middle of hearing people and the deaf community.”</i> What is it like to grow up with hearing loss?
No full textInternational audienceObjective: Hearing loss in children and adolescents can significantly impact social interactions, language development, and emotional well-being, often leading to academic and mental health challenges. This qualitative, retrospective study examines how individuals reflect on their experiences growing up with hearing loss, including the challenges they faced, the support they received, and the coping strategies they developed over time.Design and study sample: Participants aged 16 and older with personal experiences of hearing loss were recruited through audiology services in England and Scotland (UK), as well as community and online channels. Nineteen semi-structured interviews were conducted in person or online, following a flexible approach to explore participants’ retrospective accounts of growing up with hearing loss. Reflexive thematic analysis was used to identify, refine, and review themes, ensuring diverse perspectives were captured through collaborative analysis.Results: Interrelated themes were identified from participants’ reflections of growing up with hearing loss, showing how they continually adapt and reshape their experiences as part of an ongoing coping and adjustment process across various social contexts.Conclusions: This study highlights the lasting impacts of growing up with hearing loss on communication, social relationships, emotional well-being, and education
Thanatic Ethics: The Circulation of Bodies in Migratory Spaces: This book emerges from "Thanatic Ethics: The Circulation of Bodies in Migratory Spaces", an interdisciplinary and transdisciplinary project uniting social scientists, postcolonial scholars, and artists worldwide to raise critical issues related to the death of migrants. It urgently calls for migration studies to confront the consequences of Western governments' restrictive and necropolitical migration policies.The volume introduces thanatic ethics as a moral compass—a code of conduct that re-endows migrant deaths with meaning, ensuring they are remembered and mourned. Through diverse perspectives, contributors examine how social practices, political mobilizations, and artistic and literary representations can serve dual purposes: memorializing the dead while changing the gaze of the living on the unidentified dead. Enhancing awareness in the wider community could lead to the overturning of current migration policies.Thoughtfully organized into four sections, the book first explores how oceanic waters have been constructed as bordering agents—spaces of exclusion and death. The second section focuses on the politics of death, burial, and mourning, while the third confronts the fraught questions inherent to visualizing the Thanatic. The concluding section advances essential conversations about care, repair, and restitution.This essential text speaks to a diverse audience including scholars and students in migration studies, postcolonial studies, human rights, ethics, cultural studies, literature, and political science. It will also prove valuable for policymakers, human rights advocates, artists, and anyone concerned with the multi-layered aspects of migration. The chapters in this book were originally published as a special issue of Interventions: International Journal of Postcolonial Studies.
No full textInternational audienceThis book emerges from "Thanatic Ethics: The Circulation of Bodies in Migratory Spaces", an interdisciplinary and transdisciplinary project uniting social scientists, postcolonial scholars, and artists worldwide to raise critical issues related to the death of migrants. It urgently calls for migration studies to confront the consequences of Western governments' restrictive and necropolitical migration policies.The volume introduces thanatic ethics as a moral compass—a code of conduct that re-endows migrant deaths with meaning, ensuring they are remembered and mourned. Through diverse perspectives, contributors examine how social practices, political mobilizations, and artistic and literary representations can serve dual purposes: memorializing the dead while changing the gaze of the living on the unidentified dead. Enhancing awareness in the wider community could lead to the overturning of current migration policies.Thoughtfully organized into four sections, the book first explores how oceanic waters have been constructed as bordering agents—spaces of exclusion and death. The second section focuses on the politics of death, burial, and mourning, while the third confronts the fraught questions inherent to visualizing the Thanatic. The concluding section advances essential conversations about care, repair, and restitution.This essential text speaks to a diverse audience including scholars and students in migration studies, postcolonial studies, human rights, ethics, cultural studies, literature, and political science. It will also prove valuable for policymakers, human rights advocates, artists, and anyone concerned with the multi-layered aspects of migration
Intrinsic motivation magnifies the effects of physical activity on perceived cognitive health
No full textPreprint uploaded on SportRχiv, preprint repository dedicated to sport, exercise, performance, and health research.International audienceObjective: Among its health benefits, physical activity improves cognitive health, but the strength of this association remains heterogeneous across studies. While previous research focused on structural factors of physical activity as potential moderating factors (e.g., duration, type), we aimed to examine whether the type of motivation (i.e., intrinsic versus extrinsic forms of motivation) could moderate the strength of the association between physical activity and cognitive health.Methods: Participants were 512 Canadian students (72% female and a mean age = 20 ± 5 years). Seven days after assessing their intrinsic and more extrinsic motivations toward physical activity, moderate-to-vigorous physical activity and perceived cognitive health were measured by questionnaire. Linear regression models were used to examine the moderating effect of motivation on the association between physical activity and cognitive health.Results: Intrinsic motivation moderated the association between moderate-to-vigorous physical activity and self-reported cognitive health (b = .12, = .04; .20, p = .004). As hypothesized, simple slope analyses showed that the association between moderate-to-vigorous physical and cognitive health was positive when intrinsic motivation was high (at sample mean + 1SD, b = .14, 95CI = .03; .25, p& .013), but not significant when intrinsic motivation was low (at sample mean - 1SD, b = -.09, 95CI = -.24; .06, p = .220). However, the moderating effect of extrinsic forms motivation was not significant (ps. > .071).Conclusion: In addition to structural aspects of physical activity, it is important to consider motivation toward physical activity when examining its effect on cognitive health
Highly active Ptx(SnO2)100-x/C catalysts towards the hydrogen oxidation reaction and tolerant to the presence of carbon monoxide
No full textInternational audiencePtxSnO2. Pt and Sn are slightly alloyed (5% to 8%) in nanoparticles. From XPS study the Sn 3d peaks present a shift towards lower binding energy values, indicating clearly an electron transfer from Pt(PtSn) towards SnO2 (electronic metal support interaction − EMSI). The incorporation of SnO2 into Pt enhances the catalytic activity towards the HOR at 0.02 V vs. RHE. The mass activity doubles, increasing from 147 mA mg −1 Pt for Pt/C to 286 mA mg− 1Pt for Pt50(SnO2)50/C, while the specific activity increases fourfold, from 0.33 mA cm− 2 Pt to 1.33 mAcm− 2 Pt . These enhancements are attributed to EMSI. Ptx(SnO2)100-x/C catalysts exhibit lower onset potentials for COads removal compared to Pt/C, both in the absence and presence of hydrogen. The high rate of CO removal is attributed to the bifunctional mechanism, while the shift of the COads oxidation onset potential towards lower values from a ligand effect. At 60 ◦C, all catalysts show activity for the HOR from 0.05 V vs. RHE in the presence of CO. Among them, Pt50(SnO2)50/C demonstrates the highest HOR activity and the greatest CO tolerance
On the morphology of buckling structures in a controlled-thickness gradient: Finite element method and experimental studies
No full textInternational audienceWe investigated straight-sided and telephone cord buckles on stressed nickel thin films deposited by ion beam sputtering on polycarbonate substrate and exhibiting a controlled thickness gradient. It is experimentally observed that the height of the straight-sided buckles aligned parallel to the thickness gradient decreases as the film thickness increases. When these buckles are oriented perpendicular to the gradient, they result in an asymmetrical profile with a maximum deflection shifted towards the thinner part of the film. Additionally, we explore the characteristics of telephone cord buckles, showing that their wavelength decreases as the local film thickness decreases. Finite elements method simulations were performed to systematically explore the influence of various thickness gradients on buckles. The numerical results are presented, compared to the experimental results and discussed
A la recherche du "moment de conversion" : Les apports de l'approche par les Capabilités au déploiement d'une mobilité professionnelle "préventive"
No full textInternational audienceNotre contribution explore le lien entre l’accompagnement par les organisations de la mobilité professionnelle des salariés et la prévention de l’usure professionnelle. En mobilisant l’approche par les Capabilités, nous cherchons à décrire les dynamiques individuelles produites par le déploiement d’une instrumentation de la mobilité et à en comprendre ses effets. Une étude qualitative a été menée au sein de trois terrains de recherche. 53 entretiens ont été conduits, permettant de croiser le regard de salariés ayant vécu une mobilité à celui de salariés ayant formulé le souhait de ne pas changer de poste de travail. Les résultats mettent en évidence l’existence d’un « moment de conversion » qui se produit lorsque le « vouloir » (aspiration à la mobilité) et le « pouvoir » (effectivité des moyens d’action) des salariés se rejoignent. La recherche révèle le rôle clé joué par l’instrumentation pour faciliter cette conjonction et pointe que c’est dans son interaction avec les acteurs organisationnels, notamment les managers de proximité, qu’elle donne toute son efficacité
Influence of applied deformation on magnetic properties of ferromagnetic Ni60Fe40 thin films deposited on polymeric substrate
No full textInternational audienceThe magnetic behaviour of a material can be altered by stresses and defects. As in polycrystalline thin films stress can be measured in situ during a deformation test using X-ray diffraction, we have developed an experimental setup that combines multiple techniques to measure stresses and analyse both mechanical and magnetic behaviours. The capabilities of our experimental setup are presented via the results obtained on a ferromagnetic Ni60Fe40 thin film (20 nm thick) deposited on a polymeric substrate. In order to cover the elastic and the cracking regimes, the films have been subjected to controlled biaxial tensile tests, i.e. two deformation paths, one to create cracks parallel to the applied magnetic field (H), and a second to create cracks perpendicular to H. The evolutions of the hysteresis loops, the measured stress, the damage and the cracking are discussed as functions of the applied deformation. In particular, there is evidence that the measured stress and magnetisation cycles are related by magneto-elastic effects, while the orientation of the cracks relative to the direction of the applied magnetic field shows a magnetic in-plane anisotropy. The stresses distribution in the ferromagnetic Ni60Fe40 thin film is clearly the main factor affecting magnetic behaviour, while crack creation and propagation have a negligible effect.Full paper (Surf Coat Tech – abstract number from ICMCTF: CM2-2-ThA-1)
Évaluation métrologique et optimisation des protocoles d'analyses d'essais mécaniques par tomographie RX et corrélation volumique
No full textThe present manuscript focuses on the optimization of the coupling between X-ray Computed Tomography (XCT) and Digital Volume Correlation (DVC). The association of these techniques provides access to the internal displacement fields of materials, enabling the three-dimensional study of deformation phenomena and damage mechanisms. However, their implementation presents several methodological and technological challenges. In addressing these challenges, a methodology has been developed to efficiently and rapidly quantify the errors associated with DVC applied to X-ray tomography, thereby assessing the reliability of the obtained measurements. Based on this approach, a new algorithm has been designed to mitigate one of the main systematic errors in DVC, related to interpolation, thus improving the accuracy of the computed displacement fields. Furthermore, the influence of tomographic acquisition parameters on DVC performance has been investigated to optimise these parameters and reduce acquisition time while ensuring satisfactory metrological performance. Finally, the developed approaches have been applied to in situ mechanical testing using X-ray tomography to assess the feasibility of high temporal resolution DVC-based tracking of internal displacement fields. This work paves the way for the study of fast-evolving phenomena in X-ray tomography using laboratory-based systems.Le travail présenté dans ce manuscrit porte sur l’optimisation du couplage de la tomographie par rayons X et la Corrélation d’Images Volumiques (CIV). L'association de ces techniques permet d’accéder aux champs de déplacement internes des matériaux et d’étudier en trois dimensions les phénomènes de déformation ainsi que les mécanismes d’endommagement. Toutefois, leur mise en œuvre soulève plusieurs défis, tant sur le plan méthodologique que technologique. Dans ce contexte, une méthodologie a été développée pour quantifier efficacement et rapidement les erreurs associées à la CIV appliquée à la tomographie RX et ainsi évaluer la fiabilité des mesures obtenues. Sur cette base, un nouvel algorithme a été développé afin de limiter l’une des principales erreurs systématiques de la CIV, liée à l’interpolation, améliorant ainsi la justesse des champs de déplacement calculés. Par ailleurs, l’influence des paramètres d’acquisition tomographique sur les performances de la CIV a été étudiée dans le but d’optimiser ces paramètres et de réduire le temps d’acquisition, tout en garantissant des performances métrologiques satisfaisantes. Enfin, les développements réalisés ont été appliqués à des essais mécaniques en tomographie in situ afin d’évaluer la faisabilité d’un suivi par CIV des champs de déplacement internes avec une haute résolution temporelle. Ces travaux ouvrent ainsi la voie à l’étude de phénomènes rapides en tomographie RX sur des équipements de laboratoire