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The Southern Man People in Western Han China: Manuscript Evidence from Zoumalou and Hujia Caochang
No full textInternational audienceAbstract The political importance of the Southern Man peoples (Nan Man 南蠻 ) and the process of their integration into the Sinitic empire are usually dated back to the Early Medieval period. However, the past thirty years have witnessed numerous excavations of sites containing manuscripts in the Middle Yangtze area, more specifically in Zhangjiashan, Zoumalou, and recently in Hujia caochang. These documents reveal a more complex picture of the Man and attest to their presence and importance as early as the Western Han, and most certainly earlier. The aim of this article is to identify the Man’s place in the sources, and to analyze the range of measures – administrative, fiscal, judicial, social – put in place to control them and/or negotiate their presence. Here, I propose to analyze the dual importance, of the Man, and of their control by the local administration. First, we will review what both medieval history and modern historiography have to say about the Man. We will then look at the potential but still limited contribution of material culture, by mentioning a few burials and insignia attributed to the Man. We will eventually analyze what the Zoumalou and Hujia caochang manuscripts tell us about the practices implemented by the regional administration to manage the problems, real or supposed, posed by the Man
MANOCCA: a robust and computationally efficient test of covariance in high-dimension multivariate omics data
No full textInternational audienceMultivariate analysis is becoming central in studies investigating high-throughput molecular data, yet, some important features of these data are seldom explored. Here, we present MANOCCA (Multivariate Analysis of Conditional CovAriance), a powerful method to test for the effect of a predictor on the covariance matrix of a multivariate outcome. The proposed test is by construction orthogonal to tests based on the mean and variance and is able to capture effects that are missed by both approaches. We first compare the performances of MANOCCA with existing correlation-based methods and show that MANOCCA is the only test correctly calibrated in simulation mimicking omics data. We then investigate the impact of reducing the dimensionality of the data using principal component analysis when the sample size is smaller than the number of pairwise covariance terms analysed. We show that, in many realistic scenarios, the maximum power can be achieved with a limited number of components. Finally, we apply MANOCCA to 1000 healthy individuals from the Milieu Interieur cohort, to assess the effect of health, lifestyle and genetic factors on the covariance of two sets of phenotypes, blood biomarkers and flow cytometry–based immune phenotypes. Our analyses identify significant associations between multiple factors and the covariance of both omics data
In mice and humans, the brain’s blood vessels mature postnatally to acquire barrier and contractile properties
No full textAbstract The brain dense vascular network is essential for distributing oxygen and nutrients to neural cells. The network develops during embryogenesis and leads to the formation of the endothelial blood-brain barrier (BBB). This barrier is surrounded by mural cells (pericytes and vascular smooth muscle cells (VSMCs)) and fibroblasts. Here, we compared the molecular and functional properties of brain vascular cells on postnatal day (P)5 vs. P15, via a transcriptomic analysis of purified mouse cortical microvessels (MVs) and the identification of vascular-cell-type-specific or -preferentially expressed transcripts. We found that endothelial cells (ECs), VSMCs and fibroblasts follow specific molecular maturation programs over this time period. In particular, ECs acquire P-glycoprotein (P-gP)-mediated efflux capacities. The arterial VSMC network expands, acquires contractile proteins (such as smooth muscle actin (SMA) and myosin heavy chain 11 (Myh11)) and becomes contractile. We also analyzed samples of human brain cortex from the early prenatal stage through to adulthood: the expression of endothelial P-gP increased at birth and Myh11 in VSMCs acts as a developmental switch (as in the mouse) at birth and up to the age of 2 of 5 years. Thus, in both mice and humans, the early postnatal phase is a critical period during which the essential properties of cerebral blood vessels (i.e. the endothelial efflux of xenobiotics and other molecules, and the VSMC contractility required for vessel tone and brain perfusion) are acquired and mature
Reconstructing the environmental conditions experienced by early modern humans at Tam Pà Ling (northeast Laos) using higher plant wax biomarkers
No full textInternational audienc
Extreme solar storms and the quest for exact dating with radiocarbon
No full textInternational audienceRadiocarbon ( 14 C) is essential for creating chronologies to study the timings and drivers of pivotal events in human history and the Earth system over the past 55,000 years. It is also a fundamental proxy for investigating solar processes, including the potential of the Sun for extreme activity. Until now, fluctuations in past atmospheric 14 C levels have limited the dating precision possible using radiocarbon. However, the discovery of solar super-storms known as extreme solar particle events (ESPEs) has driven a series of advances with the potential to transform the calendar-age precision of radiocarbon dating. Organic materials containing unique 14 C ESPE signatures can now be dated to annual precision. In parallel, the search for further storms using high precision annual 14 C measurements has revealed fine-scaled variations that can be used to improve calendar-age precision, even in periods that lack ESPEs. Furthermore, the newly identified 14 C fluctuations provide unprecedented insight into solar variability and the carbon cycle. Here, we review the current state of knowledge and share our insights into these rapidly developing, diverse research fields. We identify links between radiocarbon, archaeology, solar physics and Earth science to stimulate transdisciplinary collaboration, and we propose how researchers can take advantage of these recent developments.Since its existence was confirmed in 1940 (ref. 1), radiocarbon has been both a cornerstone for dating the past 55,000 years and a fundamental tracer of Earth system processes. Here we draw together recent developments across multiple disciplines that offer new insights into the archaeological, Earth and space sciences. We discuss how the discovery of so-called Miyake events caused by ESPEs has created opportunities for more-precise radiocarbon calibration and stimulated research programmes to measure past 14 C levels at annual resolution. We summarize how scientists can use ESPEs directly to obtain exact calendar dates using radiocarbon, and how they can leverage fine-scale variations in 14 C identified by wider annual measurement programmes for calibration more broadly. We also survey the insights that ESPEs and consequent high-precision annual 14 C measurements have provided regarding space weather and the global carbon cycle, and describe areas where further research is required to gain the greatest value from radiocarbon.</p
Le cisaillement sanguin au cours du cycle cardiaque et l’orientation ainsi que la polarité des cellules endothéliales dans l’artère carotide de souris mâles et femelles.
No full textInternational audienceIntroduction: Blood flow produces fluid shear stress (SS), a frictional force parallel to the blood flow, on the endothelial cell (EC) layer of the lumen of the vessels. ECs themselves are sensitive to this frictional force in terms of directionality and intensity. The aim of this study was to determine the physiological shear stress value during the cardiac cycle and EC polarity and orientation from blood flow in healthy male and female mouse carotid artery.Methods: Experimentation is done on anesthetized male and female 8-week-old C5BL/6J mice. In vivo measurements of maximum blood velocity and vessel diameter in diastole and systole were performed on the right common carotid artery by Doppler ultrasound imaging. Blood viscosity (total and plasmatic) and hematocrit were determined on blood samples. For SS calculation, we developed a new method assuming heterogenous blood flow, i.e., a red cell central plug flow surrounded by a peripheral plasma sheath flow, and computing SS from vessel diameter and hemodynamical measurements (maximal blood velocity, hematocrit and plasmatic viscosity).Results: Results were compared with the classical method assuming a homogenous blood flow with constant apparent total blood viscosity. EC polarity and orientation were determined ex vivo on the carotid endothelium by confocal imaging after labeling of the EC nucleus and Golgi apparatus. Diastolic and systolic SS were 6 ± 2.5 Pa and 30 ± 6.5 Pa, respectively. Total blood and plasmatic viscosity was 4 ± 0.5 cP and 1.27 cP, respectively. ECs were polarized and significantly oriented against blood flow. No sex difference was identified.</div
History and Acoustics of Preaching in Notre-Dame de Paris
No full textInternational audienceThis article investigates the audibility and intelligibility of preaching in a loud voice inside the Cathedral Notre-Dame de Paris during the Middle Ages, after the construction of the Gothic cathedral, until the late 19th century. Through this time period, the locations where oration took place changed along with religious practices inside the cathedral. Here, we combine a historical approach with room acoustic modelling to evaluate the locations inside the cathedral where one would hear sermons well. In a reverberant cathedral such as Notre-Dame, speech would be most intelligible in areas near the orator. Until the introduction of electronically amplified public address systems, speech would not be intelligible throughout the entire cathedral
Malédictions et sacralité. La conception du revêtement de l’icône de la Vierge Éléousa de Messembrie et son contexte socio-culturel
No full textInternational audienceThe icon of the Virgin Eleousa of Messembria is one of the masterpieces of Bulgarian medieval art. Its revetment, dating originally to 1341/1342, has attracted scholarly attention mainly due to the historical data contained in the dedicatory inscriptions. Taking an art historical approach, this article offers an in-depth study of the phases of the revetment's embellishment in terms of chronology, extent, and relation to the artistic developments and the socio-cultural context of the period. It traces the visual transformation of the icon, and the way in which it enriched the veneration of the holy image from the fourteenth to the first half of the nineteenth century.L’icône de la Vierge Éléousa de Messembrie constitue un des joyaux de l’art médiéval bulgare. Or son revêtement, réalisé en 1341/1342, a attiré l’attention de la communauté scientifique essentiellement en raison des données historiques contenues dans les inscriptions dédicatoires. Afin de combler cette lacune, l’article propose une étude approfondie des phases d’élaboration du revêtement, en précisant leur chronologie, les fragments concernés, leur inscription dans les évolutions artistiques et le contexte socio-culturel de l’époque. Il retrace la transformation visuelle de l’icône, mais également la façon dont elle a enrichi la vénération de l’image sainte du XIVe à la première moitié du XIXe siècle
