55 research outputs found

    The Noncommutative Harmonic Oscillator based in Simplectic Representation of Galilei Group

    Full text link
    In this work we study symplectic unitary representations for the Galilei group. As a consequence the Schr\"odinger equation is derived in phase space. The formalism is based on the non-commutative structure of the star-product, and using the group theory approach as a guide a physical consistent theory in phase space is constructed. The state is described by a quasi-probability amplitude that is in association with the Wigner function. The 3D harmonic oscillator and the noncommutative oscillator are studied in phase space as an application, and the Wigner function associated to both cases are determined.Comment: 7 pages,no figure

    Search for scalar diphoton resonances in the mass range 65-600 GeV with the ATLAS detector in pp collision data at √s = 8  TeV

    Get PDF
    A search for scalar particles decaying via narrow resonances into two photons in the mass range 65–600 GeV is performed using 20.3  fb−¹ of √s=8  TeV pp collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches

    Monitoring and data quality assessment of the ATLAS liquid argon calorimeter

    Get PDF
    The liquid argon calorimeter is a key component of the ATLAS detector installed at the CERN Large Hadron Collider. The primary purpose of this calorimeter is the measurement of electron and photon kinematic properties. It also provides a crucial input for measuring jets and missing transverse momentum. An advanced data monitoring procedure was designed to quickly identify issues that would affect detector performance and ensure that only the best quality data are used for physics analysis. This article presents the validation procedure developed during the 2011 and 2012 LHC data-taking periods, in which more than 98% of the proton-proton luminosity recorded by ATLAS at a centre-of-mass energy of 7-8 TeV had calorimeter data quality suitable for physics analysis

    Changes to the Fossil Record of Insects through Fifteen Years of Discovery

    Get PDF
    The first and last occurrences of hexapod families in the fossil record are compiled from publications up to end-2009. The major features of these data are compared with those of previous datasets (1993 and 1994). About a third of families (>400) are new to the fossil record since 1994, over half of the earlier, existing families have experienced changes in their known stratigraphic range and only about ten percent have unchanged ranges. Despite these significant additions to knowledge, the broad pattern of described richness through time remains similar, with described richness increasing steadily through geological history and a shift in dominant taxa, from Palaeoptera and Polyneoptera to Paraneoptera and Holometabola, after the Palaeozoic. However, after detrending, described richness is not well correlated with the earlier datasets, indicating significant changes in shorter-term patterns. There is reduced Palaeozoic richness, peaking at a different time, and a less pronounced Permian decline. A pronounced Triassic peak and decline is shown, and the plateau from the mid Early Cretaceous to the end of the period remains, albeit at substantially higher richness compared to earlier datasets. Origination and extinction rates are broadly similar to before, with a broad decline in both through time but episodic peaks, including end-Permian turnover. Origination more consistently exceeds extinction compared to previous datasets and exceptions are mainly in the Palaeozoic. These changes suggest that some inferences about causal mechanisms in insect macroevolution are likely to differ as well

    In vitro and in vivo anti-malarial activity of plants from the Brazilian Amazon

    Full text link

    COVID-19 and SARS-CoV-2: Despite the vaccination, new targets/drugs for treatment and the virus cycle mechanisms still have to be continually investigated

    Get PDF
    Several countries are suffering with COVID-19 second wave that has been worse than the first one. In addition, new challenges are being imposed by new mutations and their high transmissibility, such as B.1.1.7, identified in the United Kingdom, and the strains P.1 and 501Y.V2, from Brazil and South Africa, respectively. They threaten the immune effects of the new launched vaccines (eg.: Coronavax, Oxford vaccine, and Sputnik) as nobody can assure their effectiveness against all coronavirus mutants that are still ahead. Finally, vaccination of the whole population against coronavirus, as it is done for influenza in the elderly people, is financially very difficult, especially in the low-income countries. Therefore, this brief 2-page opinion comes to highlight the fact that, similar to HIV infection (AIDS), COVID-19 will need continuous research about the virus cycle mechanisms and drug design/searching for new antivirus that may treat those infected with this still unknown virus to avoid its major effects and high lethality worldwide.</p

    Selective whole-genome amplification reveals population genetics of Leishmania braziliensis directly from patient skin biopsies.

    No full text
    In Brazil, Leishmania braziliensis is the main causative agent of the neglected tropical disease, cutaneous leishmaniasis (CL). CL presents on a spectrum of disease severity with a high rate of treatment failure. Yet the parasite factors that contribute to disease presentation and treatment outcome are not well understood, in part because successfully isolating and culturing parasites from patient lesions remains a major technical challenge. Here we describe the development of selective whole genome amplification (SWGA) for Leishmania and show that this method enables culture-independent analysis of parasite genomes obtained directly from primary patient skin samples, allowing us to circumvent artifacts associated with adaptation to culture. We show that SWGA can be applied to multiple Leishmania species residing in different host species, suggesting that this method is broadly useful in both experimental infection models and clinical studies. SWGA carried out directly on skin biopsies collected from patients in Corte de Pedra, Bahia, Brazil, showed extensive genomic diversity. Finally, as a proof-of-concept, we demonstrated that SWGA data can be integrated with published whole genome data from cultured parasite isolates to identify variants unique to specific geographic regions in Brazil where treatment failure rates are known to be high. SWGA provides a relatively simple method to generate Leishmania genomes directly from patient samples, unlocking the potential to link parasite genetics with host clinical phenotypes

    Evidence for a modulatory effect of IL-10 on both Th1 and Th2 cytokine production: The role of the environment

    Get PDF
    Allergic and other immune-mediated diseases are complex disease states determined by interplay between host genetics and environmental factors. Environmental changes such as fewer infections and reduced exposure to microbial products have been suggested to have led to insufficient regulation of Th1 and Th2 immune responses, causing an increased incidence of inflammatory diseases. The objective of the present study was to investigate the effect of poor living environmental conditions on mitogen-induced production of cytokines (Th1 and Th2) by peripheral blood leukocytes in children living in urban Brazil and investigate the role of IL-10 in modifying this effect. Our data showed that the proportion of children producing Th1 and Th2 cytokines was lower among those with poor living conditions and that this finding was stronger in children producing IL-10. These results provide a possible biologic explanation for the temporal trends of increasing risk of inflammatory diseases observed in populations living in affluent countries

    Integrating SWGA and WGS genomes for population genomics.

    No full text
    (A) Map showing all 59 samples, from this study and four previously published reports, included in the analysis. (B) Zoomed view of Bahia, Brazil showing region covered by samples from this study. White point indicates position of field hospital where patients were seen. (C-D) Principal component analysis of SNP data from 59 genomes, colored by country of origin. (E) Maximum likelihood tree constructed using 877713 variants from 59 L. braziliensis genomes and the L. guyanensis outgroup, compared to the L. braziliensis reference. Branch length of outgroup was shortened for figure preparation. Tree is rooted using the L. guyanensis outgroup. The same cultured laboratory clone of L. braziliensis from Brazil was sequenced either by traditional WGS (black circle) or SWGA (white triangle). [7, 46, 8, 47]. Map data from Maps Mapbox (www.mapbox.com/about/maps) and OpenStreetMap (www.openstreetmap.org/about).</p
    corecore