Violences et spatialités du sacrifice hindou en Inde du Sud

L’article pose la question des correspondances entre champ sacré, champ social et champ spatial relatives aux expressions violentes du sacrifice et du système des castes, dans un village du sud de l’Inde. Il s’agit de voir, dans le contexte spécifique du village de Mailam au Tamil Nadu, combien les spatialités des violences du sacrifice hindou révèlent une géographie socioreligieuse idéologique de l’espace villageois, porteuse de violences symboliques qui se retrouvent dans les enjeux d’un conflit local opposant une caste dominante à une caste intouchable.This article deals with the relationship between the sacred, social and spatial manifestations of violence involved in the sacrificial and the caste system in a South Indian village. Our case study of the Mailam village of Tamil Nadu reveals that the spatiality of the sacrificial violence present in the geography of the village is both socioreligious and ideological, while underlining the symbolic nature of the violence of a local conflict between a dominant caste and a community of untouchables

Fibre gratings for hydrogen sensing

Liquid hydrogen has been intensively used in aerospace applications for the past 40 years and is of great interest for future automotive applications. Following major explosive risks due to the use of hydrogen in air, several studies were carried out in order to develop optical fibre sensors for the detection of hydrogen leakage. This paper aims at the presentation of new hydrogen sensors based on the use of fibre Bragg gratings (FBG) and long period gratings (LPG) coated by palladium nanolayers. The sensing principle based on the palladium–hydrogen interaction is presented, as well as experimental results. It is shown that both techniques could be used for hydrogen sensing but with a sensitivity enhanced by a factor up to 500 when using a LPG sensor. FBG sensors appear to be pure strain sensors and LPG sensors are mainly based on the coupling between the cladding modes and evanescent or surface plasmon waves. Preliminary results obtained with an in-fibre Mach–Zehnder interferometer configuration with in-series LPG sensors are also presented. They show potential interest to compensate for the thermal sensitivity of the fibre gratings

Work Function Describes the Electrocatalytic Activity of Graphite for Vanadium Oxidation

In many applications such as vanadium flow batteries, graphite acts as an electrocatalyst and its surface structure therefore determines the efficiency of energy conversion. Due to the heterogeneity of the material, activity descriptors cannot always be evaluated with certainty because the introduction of defects is accompanied by a change in surface chemistry. Moreover, surface defects occur in multiple dimensions, and their occurrence and influence on catalysis must be separated. In this work, we have studied the surface of graphite felt electrodes by different methods in terms of morphology and chemistry to understand the electrocatalytic activity. We then defined the interaction between the surface and the electronic structure with particular emphasis on the work function and valence band. Using model catalysts with different architectures, we established correlations between the electrocatalytic activity and the size of the conjugation and the orientation of the edges. Finally, it was possible to link the level of the work function to the electrocatalytic activity

« La nouvelle vague du militantisme de l’information » : nouveaux médias d’information en ligne, « journalistes citoyens » conservateurs et pratiques de la contre-démocratie aux États-Unis

Profitant des coupes drastiques opérées dans le journalisme traditionnel couvrant les Congrès d’État, des organisations conservatrices ont proposé à partir de la fin de années 2000 de nouveaux médias d’information en ligne leur permettant de véhiculer une idéologie articulée autour de la responsabilité fiscale et des dépenses excessives du gouvernement. Elles exploitent la fibre citoyenne des conservateurs en les encourageant à devenir des « militants de l’information », chargés de surveiller leur gouvernement local et de signaler les abus commis par des élus ne respectant pas leur engagement conservateur. Ces pratiques s’inscrivent dans l’esprit de « contre-démocratie » défini par l’historien des idées Pierre Rosanvallon, selon lequel des citoyens cherchent à s’emparer des mécanismes démocratiques pour faire entendre leur voix.Following drastic cuts in investigative journalism covering government activities, conservative organizations started offering their own online news media at the end of the 2000s, conveying an ideology focused on fiscal responsibility and a critique of the federal government’s excessive spending. These organizations tapped into the sense of civic duty of conservatives and encouraged them to become “information activists,” responsible for surveilling their local government and denouncing abuses by elected officials who failed to uphold their conservative doctrine. These “citizen journalists” inscribe in “counter-democracy,” defined by intellectual historian Pierre Rosanvallon as the principle by which citizens exploit democratic institutions to express their voices

« Chikhansink » : cartographie européenne et contre-cartographie amérindienne dans la vallée du Delaware au xviie siècle

Cet article examine la façon dont le plan d’implantation de William Penn pour sa Province a contribué à la dépossession des Lennape dans la Vallée du Delaware à partir de la fin du xviie siècle. Les nouvelles techniques cartographiques européennes, utilisant l’arpentage de la propriété et reposant sur des critères fixes de géographie et de géométrie euclidienne, impliquaient une division de l’espace et du territoire diamétralement opposée aux conceptions et aux modes de représentation amérindiens. Les entités Lennape se retrouvèrent progressivement effacées de la carte, et par conséquent du territoire. Cet article mobilise la contre-cartographie pour relire les archives coloniales, afin d’éclairer les spécificités de la cartographie amérindienne et de restaurer la centralité des Amérindiens, de leurs conceptions et de leurs pratiques dans l’histoire de la région.This essay examines the way William Penn’s settlement design for his province contributed to dispossessing the Lennape Indians in the Delaware Valley from the end of the 17th century. New European mapping techniques, by using property survey and relying on fixed geographical references and euclidian geometry, implied a division of space and territory at complete odds with indigenous conceptions and modes of representation. The Lennape were progressively erased from the map and consequently, from the territory. This essay uses counter-cartography to revisit colonial archives, in order to shed light on indigenous cartography and to reinstate the centrality of indigenous populations, their conceptions and practices in the history of the region