Notes sur la dimension immunitaire des enclaves pétrolières

Cet article se propose de réfléchir aux modes d’installation des enclaves pétrolières en milieux difficiles ; il s’attache aux procédures qui visent à prémunir l’activité extractive du potentiel de perturbation et/ou d’hostilité dont recèlent ces milieux. Dans un premier temps, et en se penchant sur le cas d’enclaves installées dans des milieux naturels hostiles à la vie, on montre en quoi le mode d'organisation des espaces extractifs est un outil important de leur immunisation : il relève d’une « architecture du vide » (Sloterdijk) qui, par la production d’un espace inclusif et autonome, permet d’affranchir l’activité des conditions et contingences des milieux où elle se déploie. Dans un second temps, on s’intéresse aux enclaves dépêchées dans des milieux « pleins » (peuplés et territorialisés), où les procédures d’immunisation s’enrichissent de mécanismes défensifs (systèmes de clôtures) et interventionnistes (pratiques de développement durable). On discute enfin de l’émergence d’un paradigme éthique qui s’enchevêtre dans les stratégies visant à garantir la permanence des activités extractives.This paper considers the ways of establishing oil enclaves in difficult environments and it focuses on procedures that aim to safeguard the extractive activity from external disturbance and/or hostility. First, in addressing the case of enclaves located in extreme environments (hostile to life), we show that the organization of enclaves is an important tool of their immunization: by producing an inclusive and autonomous space, an "architecture of vacuum "(Sloterdijk) allows to free the activity from the conditions and contingencies of the external environment. Secondly, we move to the case of enclaves established in environments that are inhabited and territorialized, where immunization procedures are enriched by defensive (fencing) and intrusive mechanisms (sustainable practices). Finally we discuss the emergence of an ethical paradigm that tangled in strategies that aim to ensure the continuity of extractive activities

Sequestration of human cytomegalovirus by human renal and mammary epithelial cells

AbstractUrine and breast milk represent the main routes of human cytomegalovirus (HCMV) transmission but the contribution of renal and mammary epithelial cells to viral excretion remains unclear. We observed that kidney and mammary epithelial cells were permissive to HCMV infection and expressed immediate early, early and late antigens within 72h of infection. During the first 24h after infection, high titers of infectious virus were measured associated to the cells and in culture supernatants, independently of de novo synthesis of virus progeny. This phenomenon was not observed in HCMV-infected fibroblasts and suggested the sequestration and the release of HCMV by epithelial cells. This hypothesis was supported by confocal and electron microscopy analyses. The sequestration and progressive release of HCMV by kidney and mammary epithelial cells may play an important role in the excretion of the virus in urine and breast milk and may thereby contribute to HCMV transmission

The effects of temperature, salinity, and the carbonate system on Mg/Ca in Globigerinoides ruber (white) : a global sediment trap calibration

This research was funded by NSF grant NSF-OCE 1260696 awarded to S. Weldeab and D.W. Lea.The Mg/Ca of planktic foraminifera Globigerinoides ruber (white) is a widely applied proxy for tropical and sub-tropical sea-surface temperature. The accuracy with which temperature can be reconstructed depends on how accurately relationships between Mg/Ca and temperature and the multiple secondary controls on Mg/Ca are known; however, these relationships remain poorly quantified under oceanic conditions. Here, we present new calibrations based on 440 sediment trap/plankton tow samples from the Atlantic, Pacific and Indian Oceans, including 130 new samples from the Bay of Bengal/Arabian Sea and the tropical Atlantic Ocean. Our results indicate temperature, salinity and the carbonate system all significantly influence Mg/Ca in G. ruber (white). We propose two calibration models: The first model assumes pH is the controlling carbonate system parameter. In this model, Mg/Ca has a temperature sensitivity of 6.0±0.8%/°C (2σ), a salinity sensitivity of 3.3±2.2%/PSU and a pH sensitivity of −8.3±7.7%/0.1 pH units; The second model assumes carbonate ion concentration ([CO32−]) is the controlling carbonate system parameter. In this model, Mg/Ca has a temperature sensitivity of 6.7±0.8%/°C, a salinity sensitivity of 5.0±3.0%/PSU and a [CO32−] sensitivity of −0.24±0.11%/μmol kg−1. In both models, the temperature sensitivity is significantly lower than the widely-applied sensitivity of 9.0±0.6%/°C. Application of our new calibrations to down-core data from the Last Glacial Maximum, considering whole ocean changes in salinity and carbonate chemistry, indicate a cooling of 2.4±1.6°C in the tropical oceans if pH is the controlling parameter and 1.5±1.4°C if [CO32−] is the controlling parameter.PostprintPeer reviewe

Aerosol indirect effects

Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterises aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth (tau a) and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. cloud droplet number concentration (N d) compares relatively well to the satellite data at least over the ocean. The relationship between (tau a) and liquid water path is simulated much too strongly by the models. This suggests that the implementation of the second aerosol indirect effect mainly in terms of an autoconversion parameterisation has to be revisited in the GCMs. A positive relationship between total cloud fraction (fcld) and tau a as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong fcld–tau a relationship, our results indicate that none can be identified as a unique explanation. Relationships similar to the ones found in satellite data between tau a and cloud top temperature or outgoing long-wave radiation (OLR) are simulated by only a few GCMs. The GCMs that simulate a negative OLR - tau a relationship show a strong positive correlation between tau a and fcld. The short-wave total aerosol radiative forcing as simulated by the GCMs is strongly influenced by the simulated anthropogenic fraction of tau a, and parameterisation assumptions such as a lower bound on Nd. Nevertheless, the strengths of the statistical relationships are good predictors for the aerosol forcings in the models. An estimate of the total short-wave aerosol forcing inferred from the combination of these predictors for the modelled forcings with the satellite-derived statistical relationships yields a global annual mean value of −1.5±0.5Wm−2. In an alternative approach, the radiative flux perturbation due to anthropogenic aerosols can be broken down into a component over the cloud-free portion of the globe (approximately the aerosol direct effect) and a component over the cloudy portion of the globe (approximately the aerosol indirect effect). An estimate obtained by scaling these simulated clearand cloudy-sky forcings with estimates of anthropogenic tau a and satellite-retrieved Nd–tau a regression slopes, respectively, yields a global, annual-mean aerosol direct effect estimate of −0.4±0.2Wm−2 and a cloudy-sky (aerosol indirect effect) estimate of −0.7±0.5Wm−2, with a total estimate of −1.2±0.4Wm−2

Human cytomegalovirus elicits fetal γδ T cell responses in utero

The fetus and infant are highly susceptible to viral infections. Several viruses, including human cytomegalovirus (CMV), cause more severe disease in early life compared with later life. It is generally accepted that this is a result of the immaturity of the immune system. γδ T cells are unconventional T cells that can react rapidly upon activation and show major histocompatibility complex–unrestricted activity. We show that upon CMV infection in utero, fetal γδ T cells expand and become differentiated. The expansion was restricted to Vγ9-negative γδ T cells, irrespective of their Vδ chain expression. Differentiated γδ T cells expressed high levels of IFN-γ, transcription factors T-bet and eomes, natural killer receptors, and cytotoxic mediators. CMV infection induced a striking enrichment of a public Vγ8Vδ1-TCR, containing the germline-encoded complementary-determining-region-3 (CDR3) δ1–CALGELGDDKLIF/CDR3γ8–CATWDTTGWFKIF. Public Vγ8Vδ1-TCR–expressing cell clones produced IFN-γ upon coincubation with CMV-infected target cells in a TCR/CD3-dependent manner and showed antiviral activity. Differentiated γδ T cells and public Vγ8Vδ1-TCR were detected as early as after 21 wk of gestation. Our results indicate that functional fetal γδ T cell responses can be generated during development in utero and suggest that this T cell subset could participate in antiviral defense in early life

Unbiased Reconstruction of a Mammalian Transcriptional Network Mediating Pathogen Responses

Models of mammalian regulatory networks controlling gene expression have been inferred from genomic data but have largely not been validated. We present an unbiased strategy to systematically perturb candidate regulators and monitor cellular transcriptional responses. We applied this approach to derive regulatory networks that control the transcriptional response of mouse primary dendritic cells to pathogens. Our approach revealed the regulatory functions of 125 transcription factors, chromatin modifiers, and RNA binding proteins, which enabled the construction of a network model consisting of 24 core regulators and 76 fine-tuners that help to explain how pathogen-sensing pathways achieve specificity. This study establishes a broadly applicable, comprehensive, and unbiased approach to reveal the wiring and functions of a regulatory network controlling a major transcriptional response in primary mammalian cells

Characterisation of analogue Monolithic Active Pixel Sensor test structures implemented in a 65 nm CMOS imaging process

Analogue test structures were fabricated using the Tower Partners Semiconductor Co. CMOS 65 nm ISC process. The purpose was to characterise and qualify this process and to optimise the sensor for the next generation of Monolithic Active Pixels Sensors for high-energy physics. The technology was explored in several variants which differed by: doping levels, pixel geometries and pixel pitches (10-25 $\mu$m). These variants have been tested following exposure to varying levels of irradiation up to 3 MGy and $10^{16}$ 1 MeV n$_\text{eq}$ cm$^{-2}$. Here the results from prototypes that feature direct analogue output of a 4$\times$4 pixel matrix are reported, allowing the systematic and detailed study of charge collection properties. Measurements were taken both using $^{55}$Fe X-ray sources and in beam tests using minimum ionizing particles. The results not only demonstrate the feasibility of using this technology for particle detection but also serve as a reference for future applications and optimisations

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe