25 research outputs found

    Effects Of 1-mcp Onthe Post-harvest Quality Of The Orange Cv. Pera Stored Under Refrigeration

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    The aim of this work was to analyse the effects of 1-MCP upon the post-harvest quality of the orange cv. Pera stored for 45 days at a temperature of 7 °C. The fruit was divided into four treatments, and then submitted to the application of three concentrations of 1-methylciclopropene (0.1, 0.5 and 1.0μL.L-1) for a period of 12 hours. The fruitwas again then stored at a temperature of 7 °C. The rate of respiration was determined, together withcoloration of the epidermis, SS, TA, ratio, vitamin C, total carotenoids, phenolic compounds, total and reducing sugars, weight loss and juice yield. The data were submitted to analysis of variance (F-Test), and the averages were analysed by regression (P≤0.05). According to the results, it could be seen that higher doses of 1-MCP may have caused chemical stress to the orangesunder evaluation, being responsible for the increasein the rate of respiration. A change in coloration of the epidermis from green to yellow/orange was delayed by the application of 1-MCP; the application of 1-MCP did not cause any alteration to such chemical characteristics as SS, TA, ratio, carotenoids, phenolic compounds or sugars.47462463

    The Genome Sequence Of Leishmania (leishmania) Amazonensis: Functional Annotation And Extended Analysis Of Gene Models

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    We present the sequencing and annotation of the Leishmania (Leishmania) amazonensis genome, an etiological agent of human cutaneous leishmaniasis in the Amazon region of Brazil. L. (L.) amazonensis shares features with Leishmania (L.) mexicana but also exhibits unique characteristics regarding geographical distribution and clinical manifestations of cutaneous lesions (e.g. borderline disseminated cutaneous leishmaniasis). Predicted genes were scored for orthologous gene families and conserved domains in comparison with other human pathogenic Leishmania spp. Carboxypeptidase, aminotransferase, and 3′-nucleotidase genes and ATPase, thioredoxin, and chaperone-related domains were represented more abundantly in L. (L.) amazonensis and L. (L.) mexicana species. Phylogenetic analysis revealed that these two species share groups of amastin surface proteins unique to the genus that could be related to specific features of disease outcomes and host cell interactions. 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    EpiReumaPt- the study of rheumatic and musculoskeletal diseases in Portugal: a detailed view of the methodology

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    Rheumatic and musculoskeletal diseases (RMD) are prevalent and leading causes of disability and consumption of healthcare and social resources. EpiReumaPt is a national population-based survey developed by the Portuguese Society of Rheumatology that aimed to estimate the prevalence of RMDs and determine their impact on function, quality of life, mental health and use of healthcare resources. This article describes in detail the design, methodology and planned analyses of EpiReumaPt. Recruitment started in September 2011 and finished in December 2013. This study involved a three-stage approach. The first step was a face-to-face survey performed by trained interviewers at the household of 10,661 subjects who where randomly selected by a stratified multistage sampling. A highly sensitive screening questionnaire for RMDs was used. Secondly, participants who screened positive (64%) for at least one RMD as well as 20% of individuals with a negative screening were invited for assessment by a rheumatologist. In total, 3,877 subjects participated in this second phase, where they were also invited to donate a blood sample to be stored at the Biobanco-IMM. History and physical examination, followed by appropriate laboratory and imaging tests were performed. At the end of the visit, the rheumatologist established a diagnosis. Finally, a team of three experienced rheumatologists reviewed all the clinical data and defined the diagnoses according to previously validated criteria. The EpiReumaPt dataset, containing data from several questionnaires, various clinical measurements and information from laboratory and imaging tests, comprises an invaluable asset for research. The large amount of information collected from each participant and the large number of participants, with a wide age range covering and being representative of the adults from the entire country, makes EpiReumaPt the largest study of RMDs performed in Portugal

    Study of Z → llγ decays at √s = 8 TeV with the ATLAS detector

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    This paper presents a study of Z → llγ decays with the ATLAS detector at the Large Hadron Collider. The analysis uses a proton–proton data sample corresponding to an integrated luminosity of 20.2 fb−1 collected at a centre-ofmass energy √s = 8 TeV. Integrated fiducial cross-sections together with normalised differential fiducial cross-sections, sensitive to the kinematics of final-state QED radiation, are obtained. The results are found to be in agreement with stateof-the-art predictions for final-state QED radiation. First measurements of Z → llγ γ decays are also reported

    Constraints on spin-0 dark matter mediators and invisible Higgs decays using ATLAS 13 TeV pp collision data with two top quarks and missing transverse momentum in the final state

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    This paper presents a statistical combination of searches targeting final states with two top quarks and invisible particles, characterised by the presence of zero, one or two leptons, at least one jet originating from a b-quark and missing transverse momentum. The analyses are searches for phenomena beyond the Standard Model consistent with the direct production of dark matter in pp collisions at the LHC, using 139 fb−1 of data collected with the ATLAS detector at a centre-of-mass energy of 13 TeV. The results are interpreted in terms of simplified dark matter models with a spin-0 scalar or pseudoscalar mediator particle. In addition, the results are interpreted in terms of upper limits on the Higgs boson invisible branching ratio, where the Higgs boson is produced according to the Standard Model in association with a pair of top quarks. For scalar (pseudoscalar) dark matter models, with all couplings set to unity, the statistical combination extends the mass range excluded by the best of the individual channels by 50 (25) GeV, excluding mediator masses up to 370 GeV. In addition, the statistical combination improves the expected coupling exclusion reach by 14% (24%), assuming a scalar (pseudoscalar) mediator mass of 10 GeV. An upper limit on the Higgs boson invisible branching ratio of 0.38 (0.30+0.13−0.09) is observed (expected) at 95% confidence level

    Search for doubly charged Higgs boson production in multi-lepton final states using 139 fb−1 of proton–proton collisions at s√ = 13 TeV with the ATLAS detector

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    A search for pair production of doubly charged Higgs bosons (H±± ), each decaying into a pair of prompt, isolated, and highly energetic leptons with the same electric charge, is presented. The search uses a proton–proton collision data sample at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 139 fb−1 recorded by the ATLAS detector during Run 2 of the Large Hadron Collider (LHC). This analysis focuses on same-charge leptonic decays, H±±→ℓ±ℓ′± where ℓ,ℓ′=e,μ,τ, in two-, three-, and four-lepton channels, but only considers final states which include electrons or muons. No evidence of a signal is observed. Corresponding upper limits on the production cross-section of a doubly charged Higgs boson are derived, as a function of its mass m(H±±), at 95% confidence level. Assuming that the branching ratios to each of the possible leptonic final states are equal, B(H±±→e±e±)=B(H±±→e±μ±)=B(H±±→μ±μ±)=B(H±±→e±τ±)=B(H±±→μ±τ±)=B(H±±→τ±τ±)=1/6, the observed (expected) lower limit on the mass of a doubly charged Higgs boson is 1080 GeV (1065 GeV) within the left-right symmetric type-II seesaw model, which is the strongest limit to date produced by the ATLAS Collaboration. Additionally, this paper provides the first direct test of the Zee–Babu neutrino mass model at the LHC, yielding an observed (expected) lower limit of m(H±±) = 900 GeV (880 GeV)

    Software performance of the ATLAS track reconstruction for LHC run 3

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    Charged particle reconstruction in the presence of many simultaneous proton–proton (pp) collisions in the LHC is a challenging task for the ATLAS experiment’s reconstruction software due to the combinatorial complexity. This paper describes the major changes made to adapt the software to reconstruct high-activity collisions with an average of 50 or more simultaneous pp interactions per bunch crossing (pileup) promptly using the available computing resources. The performance of the key components of the track reconstruction chain and its dependence on pile-up are evaluated, and the improvement achieved compared to the previous software version is quantified. For events with an average of 60 pp collisions per bunch crossing, the updated track reconstruction is twice as fast as the previous version, without significant reduction in reconstruction efficiency and while reducing the rate of combinatorial fake tracks by more than a factor two
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