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Lettres en marge : disgrâce politique et stratégies épistolaires à Byzance (seconde moitié du XIVe siècle)
No full textInternational audiencePlusieurs travaux récents ont suggéré l’existence d’un renouvellement de l’idéologie impériale byzantine au début du XVe siècle, avec l’émergence d’un discours impérial dominant laissant peu de place à l’expression d’opinions divergentes. Selon cette interprétation, cette configuration contrasterait avec la période immédiatement antérieure, sous le règne de Jean V Paléologue dans la seconde moitié du XIVe siècle. Durant le règne de cet empereur, l’emprise impériale sur le discours politique divergent aurait été plus lâche. L’expression dissidente aurait ainsi trouvé davantage d’espace pour s’exprimer. Cette communication propose de revenir sur cette lecture historiographique en analysant un corpus de lettres rédigées sous le règne de Jean V par des individus en situation de disgrâce politique. L’étude de ces correspondances permet de réévaluer l’autonomie d’expression dont jouissaient ces figures marginalisées, en révélant des stratégies d’autocensure élaborées collectivement. Ces mécanismes incluent notamment des pratiques concertées de régulation discursive, telles que la relecture mutuelle de lettres à adresser à l’empereur ou la recommandation de suspendre certains échanges, dans le but de limiter les risques politiques et de préserver la sécurité des correspondants
Whole exome sequencing identifies ABHD14A and MRNIP as novel candidate genes for developmental language disorder
No full textInternational audienceHearing impairment (HI) is a prevalent neurosensory condition globally, impacting 5% of the population, with over 50% of congenital cases attributed to genetic etiologies. In Tunisia, HI underdiagnosis prevails, primarily due to limited access to comprehensive clinical tools, particularly for syndromic deafness (SD), characterized by clinical and genetic heterogeneity. This study aimed to uncover the SD spectrum through a 14-year investigation of a Tunisian cohort encompassing over 700 patients from four referral centers (2007–2021). Employing Sanger sequencing, Targeted Panel Gene Sequencing, and Whole Exome Sequencing, genetic analysis in 30 SD patients identified diagnoses such as Usher syndrome, Waardenburg syndrome, cranio-facial-hand-deafness syndrome, and H syndrome. This latter is a rare genodermatosis characterized by HI, hyperpigmentation, hypertrichosis, and systemic manifestations. A meta-analysis integrating our findings with existing data revealed that nearly 50% of Tunisian SD cases corresponded to rare inherited metabolic disorders. Distinguishing between non-syndromic and syndromic HI poses a challenge, where the age of onset and progression of features significantly impact accurate diagnoses. Despite advancements in local genetic characterization capabilities, certain ultra-rare forms of SD remain underdiagnosed. This research contributes critical insights to inform molecular diagnosis approaches for SD in Tunisia and the broader North-African region, thereby facilitating informed decision-making in clinical practice
Les astrocytes du VLPO, acteurs clés de la régulation du sommeil: published in Médecine du Sommeil, Volume 21, Issue 4, 2024, p. 198-206
No full textInternational audienceAstrocytes are glial cells of the central nervous system, whose role in brain physiology is increasingly well understood. Recently, their involvement in sleep regulation, particularly through the regulation of extracellular adenosine levels, has been extensively studied. This purine plays a central role in sleep regulation, especially in the ventrolateral preoptic nucleus (VLPO), a key brain region involved in the promotion of slow-wave sleep. By combining in situ enzymatic quantification of adenosine levels, infrared videomicroscopy measurements of vascular reactivity, and patch-clamp recordings of neuronal activity, it has been demonstrated that these VLPO astrocytes adjust extracellular adenosine levels in response to available glucose, prostaglandin D2 (PGD2) levels, and circadian timing.Extracellular adenosine activates A2A receptors located on endothelial cells of blood vessels and sleep-promoting neurons of the VLPO, simultaneously adjusting the increase in blood flow to neuronal activity. This ensures the necessary energy supply for neuronal activation, thereby allowing optimal activation of the VLPO and promoting sleep. This gliocentric mechanism is also integrative, adapting the adenosinergic response to circadian timing, with a greater impact when sleep pressure is high compared to when it is low. Thus, VLPO astrocytes do not merely provide structural support to neurons but also play a dynamic and integrative role in the regulation of vigilance states.Les astrocytes sont des cellules gliales du système nerveux central, dont le rôle dans la physiologie cérébrale est de mieux en mieux compris. Récemment, leur implication dans la régulation du sommeil, notamment via la régulation des taux extracellulaires d’adénosine a été particulièrement étudiée. Cette purine joue en effet un rôle central dans la régulation du sommeil, en particulier au niveau du noyau préoptique ventrolatéral (VLPO), une région clé du cerveau impliquée dans la promotion du sommeil lent. En combinant des quantifications enzymatiques in situ des taux d’adénosine, des mesures en vidéomicroscopie infra rouge de la réactivité vasculaire, ainsi que des enregistrements en patch-clamp de l’activité neuronale, il a été démontré que ces astrocytes du VLPO ajustent les taux d’adénosine extracellulaires en réponse du glucose disponible, des taux de prostaglandine D2 (PGD2) et du moment circadien. L’adénosine extracellulaire active les récepteurs A2A situés au niveau des cellules endothéliales des vaisseaux sanguins et des neurones promoteurs du sommeil du VLPO, afin d’ajuster simultanément l’augmentation du flux sanguin à l'activité neuronale. Ainsi, l’apport énergétique nécessaire à l’activation neuronale est assuré, ce qui permet ainsi une activation optimale du VLPO et le sommeil. Ce mécanisme gliocentrique est également intégratif, adaptant la réponse adénosinergique au moment circadien, plus important quand la pression de sommeil est élevée, que lorsqu’elle est faible.Les astrocytes du VLPO ne se contentent donc pas de soutenir structurellement les neurones, mais jouent également un rôle dynamique et intégratif dans la régulation des états de vigilance
Vinaya and Volunteers: Updating Tradition and Initiating Change at Pushou Temple
No full textInternational audiencePushou Temple (普寿寺), located on Mount Wutai (五台山) in Shanxi province (山西省), is known as the largest Buddhist temple for women in China. It also hosts a Buddhist Institute for nuns (Zhongguo Wutaishan nizhong foxueyuan 中 国 五 台 山 尼 众 佛 学 院 ). Rebuilt in 1991, it expanded and later built another temple in 2005, Dacheng Temple (大乘寺), while also opening a charity, the Bodhi Love Association (Puti aixin xiehui 菩提爱心协会) that same year. These last two institutions are both located in Jinzhong (晋中), Shanxi. Together with a home for the elderly (Qingtai anyang yuan 清泰安养园), these institutions constitute the “Three-Plus-One” project (San jia yi jiaoyu gongcheng 三加一教育工程), born in 2006. Looking into this threefold project, one can identify several recurring themes of contemporary Chinese Buddhism, that are monastic discipline, modern education, and Buddhist philanthropy. Belonging to these themes are two movements, one that involves reviving Vinaya practices and rituals in contemporary times, as part of a revival initiated in the 1930s, and the second being the development of the religious volunteer or yigong 义工 figure after the 1980s. Although seemingly without connection, they can both be observed within Pushou Temple. Therefore, drawing from interviews and fieldwork observations, this paper argues that these two crucial movements both participate in their own way in the reconfiguration operated by contemporary Buddhism. Focusing specifically on tradition and its innovation potential, while also looking at the impact of new actors on religious practices and experiences, will lead to identifying the processes according to which this reconfiguration takes place in mainland China
Popular Science: Astronomical Data in Chinese Local Gazetteers, Using LoGaRT
No full textInternational audienceAmong the many astronomical facts included in the ‘Star Field’ (Xingye 星野) and ‘Field Allocation’ (Fenye 分野) chapters of local gazetteers are figures for the polar distance and equatorial and ecliptical width of the constellation with which a given locality is associated. Though these are ‘fixed stars’ (hengxing 恆星), the orthodox values of these measures vary from historical sky survey to another as a function of secular motion, the precession of the equinoxes, instrumentation, and observational practice. An astronomer knows this, and he knows to use the latest values, but a local historian in a time when the study of the subject was technically illegal might instead opt for antiquarian values, mix and match, or otherwise make a mess of scientific data. He might also copy and paste, propagating an error through subsequent generations and editions. This paper will examine these phenomena, identifying the origins of such data, tracing their separate transmission within the gazetteer genre, and reflecting upon differences in epistemology, presentation, and function between popular and expert astronomy. How, if at all, are survey data treated differently than astrological and historical facts? What relation do they have to the state of the field in the astral sciences? And what do these data matter to the history of a prefecture or town
Travail collectif et débat public : différences dans l’arbitrage de la politique scientifique entre les dynasties du Nord et celles du Sud
No full textInternational audienceAvant l’avènement de l’Empire, les souverains chinois avaient déjà commencé à poursuivre une politique astronomique, à l’instar des rois sages, visant à « observer les signes et octroyer les saisons ». Mais comment décideriez-vous, si vous étiez empereur, du meilleur système de concepts, de constantes et d’algorithmes pour prédire les éclipses et les positions des planètes ? Certains, à l’image de Yao 堯, ont confié ce choix aux professionnels du Bureau d’astronomie. Cependant, Christopher Cullen (2007) et Chen Meidong (2007) nous rappellent que, sous les Han (206 av. J.-C.~220 apr. J.-C.), la plupart des experts provenaient d’ailleurs, et qu’un grand nombre de réformes ont été décidées dans le cadre d’un yi 議 – une sorte de débat ou « parlement », souvent ouvert aux « cent fonctionnaires » 百官 et qualifié d’« équitable » 平, dont plusieurs transcriptions sont conservées dans les histoires dynastiques. Cette communication vise à explorer l’articulation entre le débat public et oral sur la politique scientifique de l’État et d’autres formes d’arbitrage. Je montrerai d’abord que les Wei du Nord (386-534) ont adopté une nouvelle stratégie pour établir un consensus : le recrutement de la quasi-totalité des experts au sein d’un comité de réforme, afin qu’ils expriment leurs différends en interne – et en amont – avant d’arriver ensemble à une solution unique. Cela met en lumière les enjeux du yi sous les Han et les dynasties du Sud qui ont perpétué cette pratique : dans la plupart des cas, le recours aux « parlements » se fait lors d’un conflit de valeurs entre innovation scientifique et tradition – surtout celle des Classiques confucéens – avant que la première ne soit canonisée en tant que symbole de l’État
The History of the Transparent Contemplation of Samantabhadra as Portrayed in Jamyang Sönam Gyeltsen’s Garland of Jewels — Part I — The Contemplative Transmission of the Buddhas
No full textNorthern Treasures Historie
Experimental Medicine: Inaugural Lecture delivered at the Collège de France on Thursday 15 May 2014
No full textInternational audienceExperimental medicine, founded by Claude Bernard in the nineteenth century, decisively oriented medical research and especially modern biology. Amongst other things, it shed light on the role of the immune system, in other word, the means of defence developed by the body to fight microbes.Alain Fischer’s work, at the interface between genetics, immunology, and paediatrics, consists in identifying rare diseases’ genetic and molecular bases, inherited immunodeficiencies (IID), causing vulnerability to infection, auto-inflammatory and auto-immune diseases, and sometimes cancers
Ouest himalayen au 1er millénaire de notre ère : interactions matérielles et routes de circulation
No full textInternational audienceDuring the 1st millennium CE, part of the Western Himalayas was subject to the same dynamic ofexchange that affected much of Central Asia and North India during the expansion of theHellenistic empire up to the post-Kushan groups. The aim of this presentation is to provide newdata collected in Ladakh, in particular in the Dras valley, in order to better understand themechanism of expansion of these different empires into the western Himalayas as well as thehigh mountain routes that were used for exchanges and their control apparatus. In order to detailthese dynamics, we first aim to present new ceramic and architectural data from two sites of thisperiod in the Dras Valley (Goshan Khar and Rgyalmo Khar) and one site in the Nubra Valley (DeskitThingang). We will then carry out an intra-regional analysis with other contemporaneous sites inLadakh, with the aim of understanding the different stages of expansion of these literate empires,the organization of the territory and the routes that linked all those sites. Finally, we will provide a macro-regional view of Ladakh's connections with its neighbours during the Kushan and post-Kushan periods