Journal of Next-Generation Research 5.0
Not a member yet
7559 research outputs found
Sort by
Development of Statistical-dynamical Tools for Tropical Cyclone Intensity Prediction in the Southwest Indian Ocean. 16C.7
No full textInternational audienc
Global and regional molecular epidemiology of HIV-1, 1990–2015: a systematic review, global survey, and trend analysis
No full textInternational audienceGlobal genetic diversity of HIV-1 is a major challenge to the development of HIV vaccines. We aimed to estimate the regional and global distribution of HIV-1 subtypes and recombinants during 1990–2015.We searched PubMed, EMBASE (Ovid), CINAHL (Ebscohost), and Global Health (Ovid) for HIV-1 subtyping studies published between Jan 1, 1990, and Dec 31, 2015. We collected additional unpublished HIV-1 subtyping data through a global survey. We included prevalence studies with HIV-1 subtyping data collected during 1990–2015. We grouped countries into 14 regions and analysed data for four time periods (1990–99, 2000–04, 2005–09, and 2010–15). The distribution of HIV-1 subtypes, circulating recombinant forms (CRFs), and unique recombinant forms (URFs) in individual countries was weighted according to the UNAIDS estimates of the number of people living with HIV (PLHIV) in each country to generate regional and global estimates of HIV-1 diversity in each time period. The primary outcome was the number of samples designated as HIV-1 subtypes A, B, C, D, F, G, H, J, K, CRFs, and URFs. The systematic review is registered with PROSPERO, number CRD42017067164.This systematic review and global survey yielded 2203 datasets with 383 519 samples from 116 countries in 1990–2015. Globally, subtype C accounted for 46·6% (16 280 897/34 921 639 of PLHIV) of all HIV-1 infections in 2010–15. Subtype B was responsible for 12·1% (4 235 299/34 921 639) of infections, followed by subtype A (10·3%; 3 587 003/34 921 639), CRF02_AG (7·7%; 2 705 110/34 921 639), CRF01_AE (5·3%; 1 840 982/34 921 639), subtype G (4·6%; 1 591 276/34 921 639), and subtype D (2·7%; 926 255/34 921 639). Subtypes F, H, J, and K combined accounted for 0·9% (311 332/34 921 639) of infections. Other CRFs accounted for 3·7% (1 309 082/34 921 639), bringing the proportion of all CRFs to 16·7% (5 844 113/34 921 639). URFs constituted 6·1% (2 134 405/34 921 639), resulting in recombinants accounting for 22·8% (7 978 517/34 921 639) of all global HIV-1 infections. The distribution of HIV-1 subtypes and recombinants changed over time in countries, regions, and globally. At a global level during 2005–15, subtype B increased, subtypes A and D were stable, and subtypes C and G and CRF02_AG decreased. CRF01_AE, other CRFs, and URFs increased, leading to a consistent increase in the global proportion of recombinants over time.Global and regional HIV diversity is complex and evolving, and is a major challenge to HIV vaccine development. Surveillance of the global molecular epidemiology of HIV-1 remains crucial for the design, testing, and implementation of HIV vaccines
Étude de la connectivité Internet de l’île de la Réunion
No full textThe access to the Internet of the Islands of the Indian Ocean Area has the particularity of using two long submarines cables. The routes have in common to go through one of these links and introduce a delay component that can be significant. The performance of TCP is linked to the state of the route and the delay. In the situation of Reunion Island, how does a protocol having a dependence on delay such as TCP behaves? In this thesis, we propose a study of the Internet in Reunion Island. The work aims to be able to take stock of Internet connectivity. They are oriented on the one hand to characterize the connectivity at the level of the network and on the other hand to translate these characteristics at the level of the transport layer. Thus, the works presented are based on two metrology studies on the Reunion network. The first review aims to characterize the delays and the routes taken from and to the island. This work is based on a platform of measures put in place for this purpose. A road identification tool has been developed to analyze roads to and from Reunion Island. This tool uses a geolocation database built from IP addresses encountered, associated delays and information from the Regional Internet Registries. The analysis of the results shows characteristics specific to the Réunion region. The second metrology study aims to analyze TCP flows. Metrics associated with the observation of the catches of traffic are identified in order to establish the performances of TCP but also the types of traffic entering and leaving the island. Since the volume of the intercepts is important, an analysis tool for efficient and rapid treatments has been developed. The contributions of this thesis are first of all related to the Reunionese context and are extrapolated to the Internet of the Indian Ocean Zone. This thesis is meant to be an element for a reflection with all the actors of the Internet in Reunion Island.L'accès à Internet des îles de la Zone Océan Indien a la particularité d’utiliser deux longs câbles sous-marins. Les routes ont en commun de passer par un de ces liens et d’introduire une composante de délai qui peut être significative. La performance de TCP est liée à l’état des routes et au délai. Dans la situation de l'île de la Réunion, comment se comporte un protocole ayant une dépendance au délai tel que TCP ? Dans cette thèse, nous proposons une étude de l'Internet à La Réunion. Les travaux visent à pouvoir dresser un bilan de la connectivité Internet. Ils s'orientent d'une part à caractériser la connectivité au niveau du réseau et d'autre part à traduire ses caractéristiques au niveau de la couche de transport. Ainsi, les travaux présentés reposent sur deux études de métrologie sur le réseau réunionnais. Le premier examen a pour objectif la caractérisation des délais et des routes empruntées depuis et en direction de l'île. Ces travaux reposent sur une plate-forme de mesures mise en place à cet effet. Un outil d'identification des routes a été développé afin d'analyser les chemins depuis et vers la Réunion. Cet outil utilise une base de données de géolocalisation construite à partir des adresses IP rencontrées, des délais associés et d'informations provenant des Registres Internet Régionaux. L’analyse des résultats montre des caractéristiques propres à la région Réunion. La seconde étude de métrologie vise l'analyse des flux TCP. Des métriques associées à l'observation des captures de trafic sont identifiées afin d’établir les performances de TCP mais également les types de trafic entrant et sortant de l'île. Le volume des écoutes étant important, un outil d'analyse pour des traitements efficaces et rapides a également été développé. Les contributions de cette thèse sont d'abord rattachées au contexte réunionnais et sont extrapolées vers l'internet de la Zone Océan Indien. Cette thèse se veut être un élément pour une réflexion avec l'ensemble des acteurs de l'Internet à La Réunion
Água e floresta na Reserva de Desenvolvimento Sustentável do Uatumã
No full textInternational audienc
Ebola Virus maintenance : if not (only) bats, what else?
No full textInternational audienceThe maintenance mechanisms of ebolaviruses in African forest ecosystems are still unknown, but indirect evidences point at the involvement of some bat species. Despite intense research, the main bat-maintenance hypothesis has not been confirmed yet. The alternative hypotheses of a non-bat maintenance host or a maintenance community including, or not, several bat and other species, deserves more investigation. However, African forest ecosystems host a large biodiversity and abound in potential maintenance hosts. How does one puzzle out? Since recent studies have revealed that several bat species have been exposed to ebolaviruses, the common denominator to these hypotheses is that within the epidemiological cycle, some bats species must be exposed to the viruses and infected by these potential alternative hosts. Under this constraint, and given the peculiar ecology of bats (roosting behaviour, habitat utilisation, and flight mode), we review the hosts and transmission pathways that can lead to bat exposure and infection to ebolaviruses. In contrast to the capacity of bats to transmit ebolaviruses and other pathogens to many hosts, our results indicate that only a limited number of hosts and pathways can lead to the transmission of ebolaviruses to bats, and that the alternative maintenance host, if it exists, must be amongst them. A list of these pathways is provided, along with protocols to prioritise and investigate these alternative hypotheses. In conclusion, taking into account the ecology of bats and their known involvement in ebolaviruses ecology drastically reduces the list of potential alternative maintenance hosts for ebolaviruses. Understanding the natural history of ebolaviruses is a health priority, and investigating these alternative hypotheses could complete the current effort focused on the role of bats
Monitoring muon flux variations besides and on a tunnel-boring machine
No full textInternational audienceTunnel-boring projects require a considerable amount of planning, well ahead of drilling operations. Despite these precautionary measures, unexpected ground geological features (local density variations, cavities, unstable superficial ground, instabilities induced by the driller) impose real-time adaptations of the drilling operations.The direct relation of muon flux absorption with the density of a given medium, makes muography a promising solution to provide a real-time density analysis of geological objects in front of the tunnel-boring machine (TBM). To test its applicability during the drilling of the "Grand Paris Express" subway network, a muon telescope was used in two different experiments. First it was placed besides the TBM, directed towards the drilled cylinder from a lateral perspective. It was then moved directly inside the TBM for the rest of the drilling operation. These experiments provide an unique dataset to optimize the methodology.The data interpretation remains technically challenging due to the poissonian nature of muon events. The muon flux is estimated through the averaging of point events during a limited time window, leading to possible misinterpretations of pure statistically natural fluctuations of the muons events. Numerical routines have been developed to compute the theoretical muon flux variations for different drilling trajectories, depths, and speeds, in a medium with heteregenous density.For the first experiment, good matches are obtained with experimental values. A blind analysis of the reconstructed TBM's time dependant position puts strong constraints on the time and spatial resolution of the method. For the second data set, because the telescope is moving forward and at an irregular pace, the muon flux crossing a particular geological object measured by the telescope has different directions with respect to time, allowing 3D density estimates. First attempts to reconstruct 3D density distribution of the ground, using inhomogeneous poisson likelihood, are presented
Impact des images radiologiques alvéolo-interstitielles pré-thérapeutiques sur le développement des pneumopathies induites par l'immunothérapie chez les patients atteints de cancer bronchique non à petites cellules
No full textIntroduction. Immunotherapy (IT) in the treatment of non-small cell lung cancer (NSCLC) has revealed a new toxicity profile including pneumonitis. There are often some restrictions about IT treatment of patients with prior alveolar-interstitial radiological images (AIRI). However, their presence is not always described and their role in the development of pneumonitis remains unknown. The main objective of our study was to evaluate the incidence of pneumonitis in the presence of AIRI on the CT scan before IT. The secondary objectives focused on the incidence of pneumonitis based on clinical characteristics, the comparison between initial report and rereading of scanners by associated radiologists, overall survival (OS) and progression free survival (PFS) data.Methods. A retrospective study was conducted on patients with NSCLC treated with IT. Clinical, radiological (initial CR and rereading) and treatment data were collected from computerized medical records.Results. A total of 156 patients were included, mostly men (n = 108, 69.2%). 120 patients had an initial ARAI and 23 developed a pneumonitis. The presence of ARAI on the initial CT scan was not associated with the development of a pneumonitis, however the traction bronchiectasis (TB) present before IT was a risk factor for pneumonitis (OR 0.25, 95%CI[0.71-0.86], p = 0.035). No clinical factors studied were significantly associated with the incidence of pneumonitis. The comparison between CT report and rereading by radiologists found significant differences in the presence of AIRI with coefficient of variation of 41.1% to 52.5%. The presence of interlobular septa (ILS) on the initial CT scan and the presence of symptoms in the ARAI group was associated with shorter OS (p = 0.038 and p = 0.051). PFS was shorter in the presence of ILS (HR 1.52, 95%C[1.07-2.16], p = 0.020) or micronodules (HR 1.54, 95%CI [1.07-2.22], p = 0.021). Conclusion. The association between pneumonitis and TB (associated with fibrosis), may limit the prescription of IT in this context and raises the question of the influence of microbiota and antibiotherapies on pneumonitis occurrence The great difference found in the description of pre-therapeutic AIRI between initial reports and rereading of CT scans suggests the need for a better communication with the radiologists, for example with the development of a radiologic check-list before IT.Introduction. L’immunothérapie (IT) dans le traitement du cancer bronchique non à petites cellules (CBNPC) a fait apparaître un nouveau profil de toxicité comprenant les pneumopathies immunomédiées (PIM). Des réserves sont souvent émises quant au traitement par IT des patients présentant des images radiologiques alvéolo-interstitiels (IRAI) préalables. Toutefois, leur présence n’est pas toujours décrite et leur rôle dans le développement des PIM reste inconnu. L’objectif principal de notre étude était d’étudier l’incidence des PIM en présence d’IRAI sur le scanner avant IT. Les objectifs secondaires portaient sur l’incidence des PIM en fonction des caractéristiques cliniques, la comparaison entre comptes-rendus (CR) initiaux et relecture des scanners par les radiologues associés et les données de survie globale (SG) et ans progression (SSP).Matériels et méthodes. Une étude rétrospective a été menée sur des patients atteints de CBNPC traités par IT. Les données cliniques, radiologiques (CR initiaux et relecture) et de traitement ont été collectées à partir des dossiers médicaux informatisés. Résultats. Un total de 156 patients a été inclus, principalement des hommes (n = 108, 69.2%). 120 patients avaient une IRAI initiale et 23 ont développé une PIM au total. La présence d’IRAI sur le scanner initial n’était pas associé avec le fait de développer une PIM, en revanche les bronchectasies de traction présentes avant IT étaient un facteur de risque de PIM (OR 0,25, IC95% [0,71-0,86], p = 0,035). Aucun facteur clinique étudié n’était significativement associé à l’incidence des PIM. La comparaison entre CR et relecture par les radiologues retrouvaient des différences importantes concernant la présence d’IRAI avec des coefficients de variation avant IT de 41,1 % et 52,5 % après IT. La présence de septas interlobulaires (SIL) sur le scanner initial et la présence de symptômes en cas d’IRAI était associée à une moins bonne SG (p = 0,038 et p = 0,051). La SSP était plus courte en présence de SIL (HR 1,52, IC95% [1,07-2,16], p = ,020) ou de micronodules (HR 1,54, IC95% [1,07-2,22], p = 0,021). Conclusion. L’association avec les BT, évocatrice des processus fibrosants, pourrait contraindre à limiter l’IT dans ce contexte et questionne sur l’influence du microbiote et des antibiothérapies sur la survenue de PIM. La grande différence de description d’IRAI pré-thérapeutiques doit nous inciter à améliorer la communication avec les radiologues, notamment sur les traitements envisagés et l’élaboration d’une check-list avant IT
Evaluating Ontology Completeness via SPARQL and Relations-between-classes based Constraints
No full textInternational audienceThis article first distinguishes constraints from rules, and descriptive constraints from prescriptive ones. Both kinds can be used to calculate a constraint-based completenesses (as opposed to a real-world-based completeness), i.e. evaluating how much of a knowledge base is complete with respect to some constraints, e.g. for evaluating how well this base follows given ontology design patterns or best practices. Such evaluations may also guide knowledge elicitation and modelisation. This article explores the ways constraints can be represented via relations between classes, hence via any knowledge representation language (KRL) that has an expressiveness at least equal to RDF or RDFS. Compared to the popular practice of both representing and checking constraints via queries, this approach is as simple, offers more possibilities for exploiting both knowledge and constraints, and permits the selection and use of inference engines adapted to the expressiveness of the exploited knowledge instead of the use of restricted or ad hoc constraint-validation tools. This approach is also modular in the sense it separates content from usage: the represented "content focused constraints" can then be exploited via few "content independent" queries, one for each usage and kind of constraint. This approach provides more possibilities
Conférence, Saint-Barthélémy-de-Vals (26), Centre de Culture Scientifique, Technique et Industrielle (CCSTI) de la Drôme: « Folklore et croyances autour des mégalithes dans la littérature arthurienne », juin 2012
No full textEvidence of polygenetic carbon trapping in the Oman Ophiolite: Petro-structural, geochemical, and carbon and oxygen isotope study of the Wadi Dima harzburgite-hosted carbonates (Wadi Tayin massif, Sultanate of Oman)
No full textInternational audienceThe Wadi Dima area (Oman Ophiolite) exposes partially altered to highly serpentinized harzburgites that are cross-cut by intense (>20 Vol%) carbonate veining. We identified a sequence of 3 types of carbonate veins with compositions ranging from calcite to dolomite (Mg/Ca = 0-0.85). Type 1 carbonates occur as a fine diffuse vein network, locally replacing olivine cores, penetrative into the serpentinized harzburgites. They have depleted trace elements abundances (e.g., Yb < 0.2 × C1-chondrite) relative to other Wadi Dima carbonates, exhibit negative Ce and positive Y, U anomalies and a broad range in δ13CV-PDB (-5 to -15‰) and δ18OSMOW (18 to 31‰). These compositions are consistent with precipitation after seawater-derived fluids and/or fluids in equilibrium with mantle rocks and serpentines during cooling of oceanic lithosphere (110 to 15°C). Type 2 carbonates are localized in veins, which acted as main flow paths for fluids interacting with peridotites in the exhumed Oman mantle lithosphere (50°C-10°C). The orientation of these veins is controlled by the crystallographic anisotropy of Oman mantle peridotites. Type 2 carbonates record two stages. The first involved the formation of large calcite crystals of composition similar to Type 1 carbonates (trace element depleted; δ13CV-PDB B = -4 to -9‰ and δ18OSMOW = 26 to 30‰), which during the second stage were recrystallized to form dolomite and calcite microcrystals (trace element enriched; δ13CV-PDB = -7 to -13‰ and δ18OSMOW = 29 to 32‰), after fluids sampling different sources including contributions of sediment-derived components. They were most likely formed at shallow depths and record the transition from oceanic to continental settings during late Cretaceous ophiolite obduction. Type 3 veins reactivate Type 2 veins. They comprise dominantly calcite and dolomite microcrystals (Light REE enriched patterns) with isotopic compositions (δ13CV-PDB B ~ -7 to -8‰; δ18OSMOW~ 28 to 32‰) consistent with precipitation at low temperatures (T°<30°C) from surface/meteoric fluids. Type 3 veining is probably triggered by ophiolite uplift during the Oligocene to early Miocene. Our study presents new insights into the role of the initial mantle anisotropy in the orientation of the vein network and of principal flow paths during serpentinization and carbonatization of mantle peridotites. It also highlights the highly variable carbon isotope composition of carbonates and suggest different origins for these heterogeneities: the carbon isotope composition of the early Type 1 carbonates dispersed in the poorly connected peridotites is locally modified by serpentinization reactions whilst the carbon isotope compositions of Type 2 and 3 carbonates record mixing of fluids from different sources in high flow veins