313 research outputs found

    Le mobilier en verre du site de la Grotta Piatta (Aregno, Haute-Corse) : composition chimique et chronotypologie

    Get PDF
    La Grotta Piatta est un site funéraire protohistorique découvert sur la côte Nord occidentale de la Balagne. Un nombre important de perles en verre y a été révélé. Sur les trois cent soixante-neuf pièces recueillies, une vingtaine a fait l’objet d’analyses pour déterminer leur composition ainsi que leur provenance. L’analyse a mis en évidence l’origine proche orientale de la pâte de verre utilisée comme matière première ; trois grands groupes ont été distingués, par rapport aux fondants et aux sables utilisés dans leur composition. Cependant, certains éléments ont montré des particularités. Chronologiquement, ce mobilier peut être rattaché à un contexte postérieur au iie siècle av. J.-C. et postérieur au ier siècle de notre ère, pour trois éléments se distinguant.Grotta Piatta is a funerary protohistoric site discovered in the Western Northern coast of Balagne, where a significant number of glass beads was discovered. Out of the three hundred sixty-nine parts collected, about a score have been analysed to determine their source and composition. The analysis highlighted the Near-Eastern origin of the molten glass used as raw material; three important groups were distinguished in relation to the fluxes and sands used in their composition. However, some elements showed specific. Chronologically, this furniture can be linked to a context posterior to the second century before Christ, except for three different elements posterior to the first century of our era

    Characterisation of the antibiotic profile of Lysobacter capsici AZ78, an effective biological control agent of plant pathogenic microorganisms

    Get PDF
    Determining the mode of action of microbial biocontrol agents plays a key role in their development and registration as commercial biopesticides. The biocontrol rhizobacterium Lysobacter capsici AZ78 (AZ78) is able to inhibit a vast array of plant pathogenic oomycetes and Gram-positive bacteria due to the release of antimicrobial secondary metabolites. A combination of MALDI-qTOF-MSI and UHPLC-HRMS/M was applied to finely dissect the AZ78 metabolome and identify the main secondary metabolites involved in the inhibition of plant pathogenic microorganisms. Under nutritionally limited conditions, MALDI-qTOF-MSI revealed that AZ78 is able to release a relevant number of antimicrobial secondary metabolites belonging to the families of 2,5-diketopiperazines, cyclic lipodepsipeptides, macrolactones and macrolides. In vitro tests confirmed the presence of secondary metabolites toxic against Pythium ultimum and Rhodococcus fascians in AZ78 cell-free extracts. Subsequently, UHPLC-HRMS/MS was used to confirm the results achieved with MALDI-qTOF-MSI and investigate for further putative antimicrobial secondary metabolites known to be produced by Lysobacter spp. This technique confirmed the presence of several 2,5-diketopiperazines in AZ78 cell-free extracts and provided the first evidence of the production of the cyclic depsipeptide WAP-8294A2 in a member of L. capsici species. Moreover, UHPLC-HRMS/MS confirmed the presence of dihydromaltophilin/Heat Stable Antifungal Factor (HSAF) in AZ78 cell-free extracts. Due to the production of HSAF by AZ78, cell-free supernatants were effective in controlling Plasmopara viticola on grapevine leaf disks after exposure to high temperatures. Overall, our work determined the main secondary metabolites involved in the biocontrol activity of AZ78 against plant pathogenic oomycetes and Gram-positive bacteria. These results might be useful for the future development of this bacterial strain as the active ingredient of a microbial biopesticide that might contribute to a reduction in the chemical input in agricultur

    Evolving Intelligent Reflector Surface Toward 6G for Public Health: Application in Airborne Virus Detection

    Get PDF
    While metasurface-based intelligent reflecting surfaces (IRS) are an important emerging technology for future generations of wireless connectivity in its own right, plans for the mass deployment of these surfaces motivate the question of their integration with other new and emerging technologies that would require such widespread deployment. This question of integration and the vision of future communication systems as an invaluable component for public health motivated our new concept of Intelligent Reflector-Viral Detectors (IR-VD). In this novel scheme, we propose deployment of intelligent reflectors with strips of receptor-based viral detectors placed between the reflective surface tiles. Our proposed approach encodes information of the presence of the virus by flicking the angle of the reflected beams, using time variations between the beam deviations to represent the messages. This information includes the presence of the virus, its location and load size. The article presents simulations to demonstrate the encoding process that represents the number of virus particles that have bound to the IR-VD

    HERUS: the far-IR/submm spectral energy distributions of local ULIRGs and photometric atlas

    Get PDF
    We present the Herschel-SPIRE photometric atlas for a complete flux limited sample of 43 local ultraluminous infrared galaxies (ULIRGs), selected at 60 μm by IRAS, as part of the HERschel ULIRG Survey (HERUS). Photometry observations were obtained using the SPIRE instrument at 250, 350, and 500 μm. We describe these observations, present the results, and combine the new observations with data from IRAS to examine the far-infrared spectral energy distributions (SEDs) of these sources. We fit the observed SEDs of HERUS objects with a simple parametrized modified blackbody model, where temperature and emissivity β are free parameters. We compare the fitted values to those of non-ULIRG local galaxies, and find, in agreement with earlier results, that HERUS ULIRGs have warmer dust (median temperature T = 37.9 ± 4.7 K compared to 21.3 ± 3.4 K) but a similar β distribution (median β = 1.7 compared to 1.8) to the Herschel reference sample (HRS, Cortese et al. 2014) galaxies. Dust masses are found to be in the range of 107.5–109 M⊙, significantly higher than that of HRS sources. We compare our results for local ULIRGs with higher redshift samples selected at 250 and 850 μm. These latter sources generally have cooler dust and/or redder 100-to-250  μm colours than our 60 μm-selected ULIRGs. We show that this difference may in part be the result of the sources being selected at different wavelengths rather than being a simple indication of rapid evolution in the properties of the population

    The Activation of DNA Damage Detection and Repair Responses in Cleavage-Stage Rat Embryos by a Damaged Paternal Genome

    Get PDF
    Male germ cell DNA damage, after exposure to radiation, exogenous chemicals, or chemotherapeutic agents, is a major cause of male infertility. DNA-damaged spermatozoa can fertilize oocytes; this is of concern because there is limited information on the capacity of early embryos to repair a damaged male genome or on the fate of these embryos if repair is inadequate. We hypothesized that the early activation of DNA damage response in the early embryo is a critical determinant of its fate. The objective of this study was to assess the DNA damage response and mitochondrial function as a measure of the energy supply for DNA repair and general health in cleavage-stage embryos sired by males chronically exposed to an anticancer alkylating agent, cyclophosphamide. Male rats were treated with saline or cyclophosphamide (6 mg/kg/day) for 4 weeks and mated to naturally cycling females. Pronuclear two- and eight-cell embryos were collected for immunofluorescence analysis of mitochondrial function and biomarkers of the DNA damage response: γH2AX foci, 53BP1 reactivity, and poly(ADP-ribose) polymer formation. Mitochondrial activities did not differ between embryos sired by control- and cyclophosphamide-exposed males. At the two-cell stage, there was no treatment-related increase in DNA double-strand breaks; by the eight-cell stage, a significant increase was noted, as indicated by increased medium and large γH2AX foci. This was accompanied by a dampened DNA repair response, detected as a decrease in the nuclear intensity of poly(ADP-ribose) polymers. The micronuclei formed in cyclophosphamide-sired embryos contained large γH2AX foci and enhanced poly(ADP-ribose) polymer and 53BP1 reactivity compared with their nuclear counterparts. Thus, paternal cyclophosphamide exposure activated a DNA damage response in cleavage-stage embryos. Furthermore, this damage response may be useful in assessing embryo quality and developmental competence

    Immune Thymic Profile of the MOG-Induced Experimental Autoimmune Encephalomyelitis Mouse Model

    Get PDF
    Multiple sclerosis (MS) is a chronic, immune-mediated, demyelinating disease that affects the neurons of the central nervous system. Activated T cells, specific for myelin epitopes, cross the brain barriers, and react against the myelin sheath, leading to demyelination. Since T cells are generated within the thymus, here we explored, in mice, the alterations occurring in this organ throughout the different phases of the disease. We induced experimental autoimmune encephalomyelitis (EAE) in C57BL/6 females and sacrifice them at the onset (day 16) and chronic phases of disease (day 23), along with non-induced controls. We observed thymic atrophy in EAE mice at the onset that remained until the chronic phase of disease. This atrophy was associated with a preferential loss of the CD4+CD8+ double positive thymocytes, an intermediate population between the more immature CD4-CD8- double negative and the most mature single positive thymocytes. This was accompanied by an increase in the thymic medullary/cortical ratio and by an altered expression levels of genes important for T cell survival. During the chronic phase, the thymi remained atrophic, but reacquired the normal proportion of the main four thymocyte populations and the normal medullary/cortical ratio. Importantly, at the onset phase, and accompanying these thymic alterations, EAE animals presented an increased percentage of demyelinating lesion area in the cerebellum, and an increased expression of interferon gamma (Ifng), interleukin (Il) 12a, and Il17a. This study suggests dynamic thymic alterations occurring in response to EAE, from the induction to the chronic phase, that might help to elucidate the MS pathophysiology.Foundation for Science and Technology (FCT) and COMPETE through the project EXPL/NEU-OSD/2196/2013 and by The Clinical Academic Center (2CA-Braga) through the project EXPL/001/2016. The work at ICVS/3B's has been developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER), and funded by FEDER funds through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the project POCI-01-0145-FEDER-007038. FM is an assistant researcher and recipient of an FCT Investigator grant with the reference IF/00231/2013. CN and SR are recipients of post-doctoral fellowships with the references SFRH/BPD/112001/2015 and SFRH/BPD/72710/2010, respectively, from POPH through FSE and MCTES national funds. CS-M. and SdN are recipients of Ph.D. fellowships with the references SFRH/BD/112494/2015 and PD/BD/114120/2015, respectively, from MCTES national fundsinfo:eu-repo/semantics/publishedVersio

    Developing Countries in the WTO Services Negotiations

    Full text link
    The aim of this paper is to analyse developing countries' participation so far in the current round of services negotiations under the Doha Development Agenda. The paper analyses developing countries' negotiating positions, as evidenced by their multilateral negotiating proposals; their initial offers; and, to the extent allowed by the incomplete and sketchy information available, their participation in bilateral market access negotiations. A number of basic themes are raised: the essential role of services for economic development; the high costs imposed by trade protection; the benefits of liberalization; the need to make use of the WTO forum to enhance credibility and sustain domestic regulatory reform programmes; the challenges of regulatory reform and the importance of appropriate sequencing; and the benefits arising from seeking further market access overseas in those areas where developing countries have a comparative advantage

    Incretin Receptor Null Mice Reveal Key Role of GLP-1 but Not GIP in Pancreatic Beta Cell Adaptation to Pregnancy

    Get PDF
    Islet adaptations to pregnancy were explored in C57BL6/J mice lacking functional receptors for glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP). Pregnant wild type mice and GIPRKO mice exhibited marked increases in islet and beta cell area, numbers of medium/large sized islets, with positive effects on Ki67/Tunel ratio favouring beta cell growth and enhanced pancreatic insulin content. Alpha cell area and glucagon content were unchanged but prohormone convertases PC2 and PC1/3 together with significant amounts of GLP-1 and GIP were detected in alpha cells. Knockout of GLP-1R abolished these islet adaptations and paradoxically decreased pancreatic insulin, GLP-1 and GIP. This was associated with abolition of normal pregnancy-induced increases in plasma GIP, L-cell numbers, and intestinal GIP and GLP-1 stores. These data indicate that GLP-1 but not GIP is a key mediator of beta cell mass expansion and related adaptations in pregnancy, triggered in part by generation of intra-islet GLP-1
    corecore