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Les Instructions sur la Pratique Exposant de Manière Détaillée les Préceptes Essentiels (Lag khrid gnad kyi man ngag pra khrid du bstan pa)
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Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo
No full textInternational audienceDespite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e \leq 0.3 at Gpc yr at 90% confidence level
Factors associated with human papillomavirus (HPV) virus load variations in genital infections in young women
No full textHuman papillomaviruses (HPVs) are the most oncogenic viruses known to humans, with 12 high-risk (HR) genotypes causing nearly all cervical cancers. Cytology is commonly used to screen for cervical lesions but is currently being replaced by testing for high-risk HPV (HR HPV). Although HR HPV screening has a higher sensitivity, its specificity is limited, and it is currently advised to repeat the first screening 4 to 6 months later. To increase the sensitivity of the screening triage, other biomarkers have been suggested, including HPV viral load. Indeed, since 1999, several independent studies have found an association between HR HPV viral load in cervical samples and the severity of cervical disease. Here, we further explore the determinants of variations in HPV viral load in genital infections in young adult women.We analysed samples collected in the PAPCLEAR clinical cohort for participants who were infected by HPV genotypes for which we quantified virus load using qPCR targeting 13 genotypes. We developed a Bayesian statistical model estimating the effect of covariates of interest on the HPV viral load. To analyse precisely the viral load difference between HPV genotypes, phylogenetic distances between HPVs were also integrated in the Bayesian model.Our results fail to identify an effect of anti-HPV vaccination, co-infections by multiple HPVs or tobacco smoking on the detected viral load. On the opposite, swabs contained significantly more viral copies than cervical smears. Our results also highlight that most of the viral load variance could be explained at the genotype level (80%) rather than at the individual level (20%). Our model reveals important differences in viral load detected between the different genotypes tested, with HPV16 being the highest and HPV18 the lowest. The impact of phylogenetic signal on viral load was</div
HPV detection patterns in young women from the PAPCLEAR longitudinal study: implications for HPV screening policies
No full textObjectives. HPV infections are ubiquitous. For most infections, we lose track of the presence of the virus in host in less than three years after the start of infection. The mechanisms regulating the persistence of HPV infection are still partially understood. In this work, we focus on incident HPV detection in young women and we characterise the dynamics of these infections and evaluate the effect of genotype and host socio-economic factors on the duration of HPV detection and time between detection.Methods. We investigated human papillomavirus (HPV) genotype detection patterns in 182 young women in Montpellier, France. We relied on SPF 10 -LiPA25 screening assay for the simultaneous detection of 25 HPV genotypes. We used survival analysis tools with frailty effects to investigate the contribution of viral and host factors to variations in the time of HPV detectability, time of first incident detection, and time before re-detection.Results. Women of the PAPCLEAR cohort experienced numerous positive HPV events, including frequent redetection of the same genotype. We retrieve classical results that HR-genotypes are detected for longer duration than LR-genotypes. HR-genotypes were also more liekly to be detected than LR-genotypes during the follow-up. The number of lifetime sexual partner was strongly associated with increased risk of new positive detection while vaccination was related to a lower risk of displaying incident infections. Covariates related to socio-economic difficulties were associated with longer duration of HPV positivity.Conclusions. Young women display numerous event of HPV detection, with frequent codetections of multiple genotypes at the same time and redetection of the same type after periods of no detection.These new detection are almost certainly the result of new acquisition from sexual partners, with little evidence of re-emergence of latent infections. A better characterisation of transient infections might help unveil doubts and misconception on HPV physiopathology, favouring adherence to preventive policies.</div
Sources et méandres des lettres grecques. Textes, manuscrits et éditionsde sources patristiques et byzantines
No full textInternational audienceOn the occasion of the eighty-year anniversary of the founding of the « Sources Chrétienne » series, the authors of the present volume deal with various aspects of the dissemination of patristic and Byzantine texts. They discuss translation as an expression of cultural transfer, with particular interest in the role of mediators. Different forms of reception of the texts are also examined. The manuscript tradition and the compilation of collections provide information on the dissemination, circulation and use of texts. From a literary point of view, the revision and rewriting of texts is examined through the lens of intertextuality. Through philological analysis, linguistic elements of particular interest are highlighted. Covering a wide range of topics, from patristics to hagiology and epistolography, and employing different approaches, the authors of this volume make us rethink how texts are born, interact, change and circulate through the centuries
Conservation of antiviral systems across domains of life reveals immune genes in humans
No full textInternational audienceDeciphering the immune organization of eukaryotes is of importance for human health and for the understanding of ecosystems. The recent discovery of dozens novel antiphage systems revealed that various eukaryotic immune proteins originate from prokaryotic antiphage systems. Whether antiphage proteins of bacteria can be utilized to discover immune proteins in eukaryotes remains unexplored. Here, we use a phylogenydriven approach to uncover novel eukaryotic immune proteins by searching for homologs of bacterial antiphage systems. We demonstrate that proteins displaying sequence similarity with recently discovered antiphage systems are widespread in eukaryotes, and maintain a role in immunity in humans. Two eukaryotic proteins of the anti-transposon piRNA pathway are evolutionary linked to the antiphage system Mokosh. We uncover and experimentally validate human antiviral genes which are related to the Eleos and Lamassu prokaryotic systems. Our work illustrates how comparative genomics of immune mechanisms can be employed to uncover defence genes in eukaryotes
The ecology, subsistence and diet of ~45,000-year-old Homo sapiens at Ilsenhöhle in Ranis, Germany
No full textInternational audienceAbstract Recent excavations at Ranis (Germany) identified an early dispersal of Homo sapiens into the higher latitudes of Europe by 45,000 years ago. Here we integrate results from zooarchaeology, palaeoproteomics, sediment DNA and stable isotopes to characterize the ecology, subsistence and diet of these early H. sapiens . We assessed all bone remains ( n = 1,754) from the 2016–2022 excavations through morphology ( n = 1,218) or palaeoproteomics (zooarchaeology by mass spectrometry ( n = 536) and species by proteome investigation ( n = 212)). Dominant taxa include reindeer, cave bear, woolly rhinoceros and horse, indicating cold climatic conditions. Numerous carnivore modifications, alongside sparse cut-marked and burnt bones, illustrate a predominant use of the site by hibernating cave bears and denning hyaenas, coupled with a fluctuating human presence. Faunal diversity and high carnivore input were further supported by ancient mammalian DNA recovered from 26 sediment samples. Bulk collagen carbon and nitrogen stable isotope data from 52 animal and 10 human remains confirm a cold steppe/tundra setting and indicate a homogenous human diet based on large terrestrial mammals. This lower-density archaeological signature matches other Lincombian–Ranisian–Jerzmanowician sites and is best explained by expedient visits of short duration by small, mobile groups of pioneer H. sapiens
Multi-method dating reveals 200 ka of Middle Palaeolithic occupation at Maras rock shelter, Rhône Valley, France
No full textInternational audienceThe emergence of the Middle Palaeolithic, and its variability over time and space are key questions in the field of prehistoric archaeology. Many sites have been documented in the south-eastern margins of the Massif central and the middle Rhône valley, a migration path that connects Northern Europe with the Mediterranean. Well-dated, long stratigraphic sequences are essential to understand Neanderthals dynamics and demise, and potential interactions with Homo sapiens in the area, such as the one displayed at the Maras rock shelter (“Abri du Maras”). The site is characterised by exceptional preservation of archaeological remains, including bones dated using radiocarbon ( 14 C) and teeth using electron spin resonance combined with uranium series (ESR/U-series). Optically stimulated luminescence was used to date the sedimentary deposits. By combining the new ages with previous ones using Bayesian modelling, we are able to clarify the occupation time over a period spanning 200,000 years. Between ca. 250 and 40 ka, the site has been used as a long-term residence by Neanderthals, specifically during three interglacial periods: first during marine isotopic stage (MIS) 7, between 247 ± 34 and 223 ± 33 ka, and then recurrently during MIS 5 (between 127 ± 17 and 90 ± 9 ka) and MIS 3 (up to 39,280 cal BP)