362 research outputs found

    Polarisation at NLO in WZ production at the LHC

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    The pair production of a WW and a ZZ boson at the LHC is an important process to study the triple-gauge boson couplings as well as to probe new physics that could arise in the gauge sector. In particular the leptonic channel pp→W±Z→3ℓ+Îœ+Xp p \to W^\pm Z\to 3\ell +\nu + X is considered by ATLAS and CMS collaborations. Polarisation observables can help pinning down new physics and give information on the spin of the gauge bosons. Measuring them requires high statistics as well as precise theoretical predictions. We define in this contribution fiducial polarisation observables for the WW and ZZ bosons and we present theoretical predictions in the Standard Model at next-to-leading order (NLO) including QCD as well as NLO electroweak corrections, the latter in the double-pole approximation. We also show that this approximation works remarkably well for W±ZW^\pm Z production at the LHC by comparing to the full results.Comment: 6 pages, 2 figures, 2 tables. Contribution to the proceedings of the 54th Rencontres de Moriond, EW interactions and unified theory, March 16-23 2019, La Thuile, Ital

    Fiducial polarization observables in hadronic WZ production: A next-to-leading order QCD+EW study

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    We present a study at next-to-leading-order (NLO) of the process pp→W±Z→ℓΜlℓâ€Č+ℓâ€Č−pp \to W^\pm Z \to \ell \nu_l \ell'^+ \ell'^-, where ℓ,ℓâ€Č=e,ÎŒ\ell,\ell' =e, \mu, at the Large Hadron Collider. We include the full NLO QCD corrections and the NLO electroweak (EW) corrections in the double-pole approximation. We define eight fiducial polarization coefficients directly constructed from the polar-azimuthal angular distribution of the decay leptons. These coefficients depend strongly on the kinematical cuts on the transverse momentum or rapidity of the individual leptons. Similarly, fiducial polarization fractions are also defined and they can be directly related to the fiducial coefficients. We perform a detailed analysis of the NLO QCD+EW fiducial polarization observables including theoretical uncertainties stemming from the scale variation and parton distribution function uncertainties, using the fiducial phase space defined by the ATLAS and CMS experiments. We provide results in the helicity coordinate system and in the Collins-Soper coordinate system, at a center-of-mass energy of 13 TeV. The EW corrections are found to be important in two of the angular coefficients related to the ZZ boson, irrespective of the kinematical cuts or the coordinate system. Meanwhile, those EW corrections are very small for the W±W^\pm bosons.Comment: Substantial improvement after useful comments from the anonymous referee: Numerical results for the EW corrections to the cross sections and distributions shifted by -5 (-2)% for ATLAS (CMS) cuts after fixing a bug in the momentum assignment in some cut and histogram routines; results for polarization observables marginally affected, hence conclusions for them unchanged; published versio

    Full NLO massive gauge boson pair production at the LHC

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    Electroweak gauge boson pair production is a very important process at the LHC as it probes the non-abelian structure of electroweak interactions and is a background process for many searches. We present full next-to-leading order predictions for the production cross sections and distributions of on-shell massive gauge boson pair production in the Standard Model, including both QCD and electroweak corrections. The hierarchy between the ZZ, WW and WZ channels, observed in the transverse momentum distributions, will be analyzed. We will also present a comparison with experimental data for the total cross sections including a study of the theoretical uncertainties.Comment: 4 pages, 4 figures. Proceeding of the inaugural conference "Windows on the Universe" (August 11-17, Quy Nhon, Vietnam) including updated results compared to arXiv:1307.433

    Online Tracking Parameter Adaptation based on Evaluation

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    Parameter tuning is a common issue for many tracking algorithms. In order to solve this problem, this paper proposes an online parameter tuning to adapt a tracking algorithm to various scene contexts. In an offline training phase, this approach learns how to tune the tracker parameters to cope with different contexts. In the online control phase, once the tracking quality is evaluated as not good enough, the proposed approach computes the current context and tunes the tracking parameters using the learned values. The experimental results show that the proposed approach improves the performance of the tracking algorithm and outperforms recent state of the art trackers. This paper brings two contributions: (1) an online tracking evaluation, and (2) a method to adapt online tracking parameters to scene contexts.Comment: IEEE International Conference on Advanced Video and Signal-based Surveillance (2013

    Adressage de Nanomédicaments à base de squalÚne

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    Les nanoparticules de Gemcitabine-SqualÚne (Gem-Sq), synthétisées suivant le concept de squalénisation , ont montré des activités anticancéreuses trÚs supérieures à celles obtenues en présence de Gem libre. Néanmoins, leur PEGylation, c est-à-dire leur décoration par du poly(éthylÚne glycol)-squalÚne (PEG-Sq) pour augmenter leur temps de demi-vie plasmatique, s est avérée infructueuse du fait d une déstructuration colloïdale. Par ailleurs, aucune stratégie de fonctionnalisation pour effectuer un ciblage actif de cellules cancéreuses, n est à ce jour disponible. Au cours de cette thÚse, nous avons donc cherché à résoudre ces problÚmes. AprÚs une étude bibliographique portant sur la conception de nanoparticules de prodrogues lipidiques, dans le but d établir un constat récent de l état de l art dans ce domaine, nous avons proposé une voie de synthÚse pour obtenir des nanoparticules multifonctionnelles (i.e., thérapeutique, fluorescentes et ciblées) à base de Gem-Sq, et ce par co-auto-assemblage des composés conjugués de Rhodamine-Sq, Gem-Sq et Biotin-Sq. Ces nanoparticules ont montré une internalisation plus importante dans les cellules cancéreuses et une meilleure efficacité thérapeutique que les nanoparticules de Gem-Sq non-fonctionnalisées. Dans un deuxiÚme temps, nous avons apporté une solution au problÚme de la PEGylation des nanoparticules de Sq via la synthÚse et l utilisation de composés conjugués de type Gem-poly(méthacrylate de squalÚne). Ces prodrogues macromoléculaires ont été synthétisées par polymérisation radicalaire contrÎlée et plus précisément par la technique RAFT. Les nanoparticules obtenues par auto-assemblage en solution aqueuse sont stables et présentent des activités anticancéreuses importantes sur différentes lignées cellulaires. Leur PEGylation par ajout de Sq-PEG durant la formulation s est avérée possible et n a pas conduit à une déstabilisation colloïdale. Enfin, j ai participé à l élaboration d une nouvelle famille de nanoparticules de prodrogues macromoléculaires qui a consisté à faire croitre de courtes chaines de polyisoprÚne (PI) à partir de la Gem, donnant ainsi des conjugués de type Gem-PI, capables de s auto-assembler sous la forme de nanoparticules avec une activité anticancéreuse in vitro et in vivo.Gemcitabine-Squalene (Gem-Sq) nanoparticles have been synthesized from the squalenoylation approach and have shown superior anticancer activities compared to those obtained with free Gem. However, their PEGylation, that is their coating with poly(ethylene glycol)-squalene (PEG-Sq) in order to increase their circulation time, has been unsuccessful, leading to colloidal disassembly. In addition, to the best of our knowledge, there is not functionalization strategy yet available to perform active targeting against cancer. During this PhD thesis, we have been looking for solutions to tackle these two important problems. After a littérature survey about the design of lipidic prodrug nanoparticles, in order to establish a pretty accurate picture of the domain, we have reported a synthetic approach towards multifunctional Sq-based nanoparticles (i.e., therapeutic, fluorescent and targeted), through the co-self-assembly of the different Sq-based materials; that is Rhodamine-Sq, Gem-Sq and Biotin-Sq. These nanoparticles have demonstrated a greater internalization into cancer cells and a greater therapeutic effect than non-functionalized Gem-Sq nanoparticles. In the next step, we have provided a solution to the PEGylation issue by synthetizing Gem-poly(squalenoyl methacrylate) macromolecular prodrugs. These materials have been prepared by controlled/living radical polymerization and especially the RAFT technique. The resulting nanoparticles exhibited significant anticancer activities against various cancer cells and can be successfully PEGylated by the addition of Sq-PEG during their formulation. Eventually, I have participated to the design of a new family of macromolecular prodrugs obtained from the growing of short polyisoprene (PI) chains from Gem, leading to Gem-PI nanoparticles after self-assembly of Gem-PI. The nanoparticles led to significant anticancer activity both in vitro and in vivo.PARIS11-SCD-Bib. électronique (914719901) / SudocSudocFranceF

    HTLV-1 HBZ cooperates with JunD to enhance transcription of the human telomerase reverse transcriptase gene (hTERT)

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    <p>Abstract</p> <p>Background</p> <p>Activation of telomerase is a critical and late event in tumor progression. Thus, in patients with adult-T cell leukaemia (ATL), an HTLV-1 (Human T cell Leukaemia virus type 1)-associated disease, leukemic cells display a high telomerase activity, mainly through transcriptional up-regulation of the human telomerase catalytic subunit (hTERT). The HBZ (HTLV-1 bZIP) protein coded by the minus strand of HTLV-1 genome and expressed in ATL cells has been shown to increase the transcriptional activity of JunD, an AP-1 protein. The presence of several AP-1 binding sites in the hTERT promoter led us to investigate whether HBZ regulates hTERT gene transcription.</p> <p>Results</p> <p>Here, we demonstrate using co-transfection assays that HBZ in association with JunD activates the hTERT promoter. Interestingly, the -378/+1 proximal region, which does not contain any AP-1 site was found to be responsible for this activation. Furthermore, an increase of hTERT transcripts was observed in cells co-expressing HBZ and JunD. Chromatin immunoprecipitation (ChIP) assays revealed that HBZ, and JunD coexist in the same DNA-protein complex at the proximal region of hTERT promoter. Finally, we provide evidence that HBZ/JunD heterodimers interact with Sp1 transcription factors and that activation of hTERT transcription by these heterodimers is mediated through GC-rich binding sites for Sp1 present in the proximal sequences of the hTERT promoter.</p> <p>Conclusion</p> <p>These observations establish for the first time that HBZ by intervening in the re-activation of telomerase, may contribute to the development and maintenance of the leukemic process.</p

    The Filling Dynamics of an Estuary: From the Process to the Modelling

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    The aim of this chapter is to summarise the main hydrosedimentary processes that take place in estuaries and to present different approaches for their modelling. Section 2 is dedicated to the description of the physical processes involved in estuaries. Section 3 presents the classical (single phase) approach focussing on different ways to model the bed evolutions; the rheological and erosion properties of mud are discussed. Section 4 deals with the two-phase model for sediment transport. Several applications are presented. Finally, the shortcomings of each modelling strategy are discussed and the perspectives are given in section 5

    DPPA2 and DPPA4 are necessary to establish a 2C‐like state in mouse embryonic stem cells

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    After fertilization of the transcriptionally silent oocyte, expression from both parental chromosomes is launched through zygotic genome activation (ZGA), occurring in the mouse at the 2-cell (2C) stage. Among the first elements to be transcribed are the Dux gene, the product of which induces a wide array of ZGA genes, and a subset of evolutionary recent LINE-1 retrotransposons that regulate chromatin accessibility in the early embryo. The maternally inherited factors that activate Dux and LINE-1 transcription have so far remained unknown. Mouse embryonic stem cells (mESCs) recapitulate some aspects of ZGA in culture, owing to their ability to cycle through a 2C-like stage when Dux, its target genes, and LINE-1 integrants are expressed. Here, we identify the paralog proteins DPPA2 and DPPA4 as necessary for the activation of Dux and LINE-1 expression in mESCs. Since their encoding RNAs are maternally transmitted to the zygote, it is likely that these factors are important upstream mediators of murine ZGA

    KRAB zinc finger protein ZNF676 controls the transcriptional influence of LTR12-related endogenous retrovirus sequences.

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    BACKGROUND: Transposable element-embedded regulatory sequences (TEeRS) and their KRAB-containing zinc finger protein (KZFP) controllers are increasingly recognized as modulators of gene expression. We aim to characterize the contribution of this system to gene regulation in early human development and germ cells. RESULTS: Here, after studying genes driven by the long terminal repeat (LTR) of endogenous retroviruses, we identify the ape-restricted ZNF676 as the sequence-specific repressor of a subset of contemporary LTR12 integrants responsible for a large fraction of transpochimeric gene transcripts (TcGTs) generated during human early embryogenesis. We go on to reveal that the binding of this KZFP correlates with the epigenetic marking of these TEeRS in the germline, and is crucial to the control of genes involved in ciliogenesis/flagellogenesis, a biological process that dates back to the last common ancestor of eukaryotes. CONCLUSION: These results illustrate how KZFPs and their TE targets contribute to the evolutionary turnover of transcription networks and participate in the transgenerational inheritance of epigenetic traits
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