349 research outputs found

    Orchidaceae no município de Vitória da Conquista, Bahia: lista de espécies e similaridade florística entre áreas da Bahia e Minas Gerais

    Get PDF
    Here we present a survey of Orchidaceae from Vitória da Conquista, Brazil and an analysis of the floristic similarity among ten areas in Bahia and Minas Gerais. Fourty-four species of orchids were found in the municipality.  Among the species found, two are new occurrences for the Northeast region of Brazil, Acianthera panduripetala and Specklinia hymenantha, and one is a new occurrence for the state of Bahia, Pabstiella seriata. Analyzes were conducted using the UPGMA algorithm, Jaccard and Dice coefficient and Correspondence Analysis. The cluster analysis revealed low similarity rates, except for Serra Negra + Ibitipoca State Park. Two groups were formed: one group of dry forest areas and another group encompassing the Rupestrian Fields and Ombrophilous Forest areas of the two states. The results suggest that the areas of the same phytophysiognomy are more related to each other than to the vegetation of the same state.Se presenta el levantamiento de las Orchidaceae de Vitória da Conquista, Brasil, y un análisis de similitud florística entre diez áreas de Bahia y Minas Gerais. Se encontraron en el municipio un total de 44 especies de orquídeas, con dos nuevos registros para el nordeste brasileño, Acianthera panduripetala y Specklinia hymenantha, además de un nuevo registro para el estado de Bahia, Pabstiella seriata. Se realizaron análisis utilizando el algoritmo UPGMA, coeficiente de Jaccard y Dice, y Análisis de Correspondencia. El análisis de agrupamiento reveló bajos índices de similitud, excepto para Serra Negra + Parque Estadual do Ibitipoca. Dos grupos fueron formados: Uno de áreas de Bosques secos y otro que incluye las áreas de Campos Rupestres y de Bosques Ombrófilos de los dos estados. Los resultados sugieren que las áreas con la misma fitofisionomía están más relacionadas entre sí, que con la vegetación del mismo estadoAqui, apresentamos o levantamento das Orchidaceae de Vitória da Conquista, Brasil, e uma análise da similaridade florística entre dez áreas da Bahia e Minas Gerais. Foram encontradas no município 44 espécies de orquídeas, sendo duas novas ocorrências para o Nordeste brasileiro, Acianthera panduripetala e Specklinia hymenantha, além de uma nova ocorrência para o estado da Bahia, Pabstiella seriata. Foram conduzidas análises utilizando o algoritmo UPGMA, coeficiente de Jaccard e Dice, e análise de correspondência. A análise de agrupamento revelou baixos índices de similaridade, exceto para Serra Negra + Parque Estadual do Ibitipoca. Dois grupos se formaram: um de áreas de Florestas Secas e outro grupo que inclui as áreas de Campos Rupestres e de Floresta Ombrófila dos dois estados. Os resultados sugerem que as áreas de mesma fitofisionomia estão mais relacionadas entre si do que com a vegetação do mesmo estado

    Social Networks Shape the Transmission Dynamics of Hepatitis C Virus

    Get PDF
    Hepatitis C virus (HCV) infects 170 million people worldwide, and is a major public health problem in Brazil, where over 1% of the population may be infected and where multiple viral genotypes co-circulate. Chronically infected individuals are both the source of transmission to others and are at risk for HCV-related diseases, such as liver cancer and cirrhosis. Before the adoption of anti-HCV control measures in blood banks, this virus was mainly transmitted via blood transfusion. Today, needle sharing among injecting drug users is the most common form of HCV transmission. Of particular importance is that HCV prevalence is growing in non-risk groups. Since there is no vaccine against HCV, it is important to determine the factors that control viral transmission in order to develop more efficient control measures. However, despite the health costs associated with HCV, the factors that determine the spread of virus at the epidemiological scale are often poorly understood. Here, we sequenced partial NS5b gene sequences sampled from blood samples collected from 591 patients in São Paulo state, Brazil. We show that different viral genotypes entered São Paulo at different times, grew at different rates, and are associated with different age groups and risk behaviors. In particular, subtype 1b is older and grew more slowly than subtypes 1a and 3a, and is associated with multiple age classes. In contrast, subtypes 1a and 3b are associated with younger people infected more recently, possibly with higher rates of sexual transmission. The transmission dynamics of HCV in São Paulo therefore vary by subtype and are determined by a combination of age, risk exposure and underlying social network. We conclude that social factors may play a key role in determining the rate and pattern of HCV spread, and should influence future intervention policies

    First titanosaur dinosaur nesting site from the Late Cretaceous of Brazil

    Get PDF
    Titanosaurs were successful herbivorous dinosaurs widely distributed in all continents during the Cretaceous, with the major diversity in South America. The success of titanosaurs was probably due to several physiological and ecological factors, in addition to a series of morphological traits they achieved during their evolutionary history. However, the generalist nesting behaviour using different palaeoenvironments and strategies was key to accomplish that success. Titanosaur nesting sites have been found extensively around the world, with notable records in Spain, France, Romania, India, and, especially, Argentina. Here, we describe the first titanosaur nesting site from the Late Cretaceous of Brazil that represents the most boreal nesting site for South America. Several egg-clutches, partially preserved, isolated eggs and many eggshell fragments were discovered in an Inceptisol palaeosol profile of the mining Lafarge Quarry, at the Ponte Alta District (Uberaba Municipality, Minas Gerais State), corresponding to the Serra da Galga Formation (Bauru Group, Bauru Basin). Although classical mechanical preparation and CT scans have not revealed embryonic remains in ovo, the eggs and eggshell features match those eggs containing titanosaurian embryos found worldwide. The morphology of the egg-clutches and observations of the sedimentary characteristics bolster the hypothesis that these sauropods were burrow-nester dinosaurs, as was already suggested for the group based on other nesting sites. The egg-clutches distributed in two levels along the Lafarge outcrops, together with the geopalaeontological data collected, provide clear evidence for the first colonial nesting and breeding area of titanosaur dinosaurs in Brazil.Fil: Fiorelli, Lucas Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: Martinelli, Agustín Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidade Federal do Triângulo Mineiro; BrasilFil: da Silva, João Ismael. Prefeitura Municipal de Uberaba; Brasil. Universidade Federal do Triângulo Mineiro; BrasilFil: Hechenleitner, Esteban Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; Argentina. Universidad Nacional de La Rioja; ArgentinaFil: Soares, Marcus Vinícius Theodoro. Universidade Estadual de Campinas; BrasilFil: Silva Junior, Julian C. G.. Universidade de Sao Paulo; Brasil. Universidade Federal do Triângulo Mineiro; BrasilFil: da Silva, José Carlos. Associação Brasileira dos Criadores de Zebu; BrasilFil: Borges, Élbia Messias Roteli. Escola Estadual Presidente João Pinheiro; BrasilFil: Borges Ribeiro, Luiz Carlos. Universidade Federal do Triângulo Mineiro; Brasil. Associação Brasileira dos Criadores de Zebu; BrasilFil: Marconato, André. Universidade de Sao Paulo; BrasilFil: Basilici, Giorgio. Universidade Estadual de Campinas; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: da Silva Marinho, Thiago. Universidade Federal do Triângulo Mineiro; Brasi

    Nietzsches gelijk: Waarom wijsheid achteraf onbillijk is

    Get PDF
    A search is performed for a massive new vector-like quark T, with charge 2/3, that is pair produced together with its antiparticle in proton-proton collisions. The data were collected by the CMS experiment at the Large Hadron Collider in 2012 at sqrt(s) = 8 TeV and correspond to an integrated luminosity of 19.5 inverse femtobarns. The T quark is assumed to decay into three different final states, bW, tZ, and tH. The search is carried out using events with at least one isolated lepton. No deviations from standard model expectations are observed, and lower limits are set on the T quark mass at 95% confidence level. The lower limit lies between 687 and 782 GeV for all possible values of the branching fractions into the three different final states assuming strong production. These limits are the most stringent constraints to date on the existence of such a quark

    Impact of cross-section uncertainties on supernova neutrino spectral parameter fitting in the Deep Underground Neutrino Experiment

    Get PDF
    A primary goal of the upcoming Deep Underground Neutrino Experiment (DUNE) is to measure the O(10)\mathcal{O}(10) MeV neutrinos produced by a Galactic core-collapse supernova if one should occur during the lifetime of the experiment. The liquid-argon-based detectors planned for DUNE are expected to be uniquely sensitive to the νe\nu_e component of the supernova flux, enabling a wide variety of physics and astrophysics measurements. A key requirement for a correct interpretation of these measurements is a good understanding of the energy-dependent total cross section σ(Eν)\sigma(E_\nu) for charged-current νe\nu_e absorption on argon. In the context of a simulated extraction of supernova νe\nu_e spectral parameters from a toy analysis, we investigate the impact of σ(Eν)\sigma(E_\nu) modeling uncertainties on DUNE's supernova neutrino physics sensitivity for the first time. We find that the currently large theoretical uncertainties on σ(Eν)\sigma(E_\nu) must be substantially reduced before the νe\nu_e flux parameters can be extracted reliably: in the absence of external constraints, a measurement of the integrated neutrino luminosity with less than 10\% bias with DUNE requires σ(Eν)\sigma(E_\nu) to be known to about 5%. The neutrino spectral shape parameters can be known to better than 10% for a 20% uncertainty on the cross-section scale, although they will be sensitive to uncertainties on the shape of σ(Eν)\sigma(E_\nu). A direct measurement of low-energy νe\nu_e-argon scattering would be invaluable for improving the theoretical precision to the needed level.Comment: 25 pages, 21 figure

    Doping liquid argon with xenon in ProtoDUNE Single-Phase: effects on scintillation light

    Get PDF
    Doping of liquid argon TPCs (LArTPCs) with a small concentration of xenon is a technique for light-shifting and facilitates the detection of the liquid argon scintillation light. In this paper, we present the results of the first doping test ever performed in a kiloton-scale LArTPC. From February to May 2020, we carried out this special run in the single-phase DUNE Far Detector prototype (ProtoDUNE-SP) at CERN, featuring 720 t of total liquid argon mass with 410 t of fiducial mass. A 5.4 ppm nitrogen contamination was present during the xenon doping campaign. The goal of the run was to measure the light and charge response of the detector to the addition of xenon, up to a concentration of 18.8 ppm. The main purpose was to test the possibility for reduction of non- uniformities in light collection, caused by deployment of photon detectors only within the anode planes. Light collection was analysed as a function of the xenon concentration, by using the pre-existing photon detection system (PDS) of ProtoDUNE-SP and an additional smaller set-up installed specifically for this run. In this paper we first summarize our current understanding of the argon-xenon energy transfer process and the impact of the presence of nitrogen in argon with and without xenon dopant. We then describe the key elements of ProtoDUNE-SP and the injection method deployed. Two dedicated photon detectors were able to collect the light produced by xenon and the total light. The ratio of these components was measured to be about 0.65 as 18.8 ppm of xenon were injected. We performed studies of the collection efficiency as a function of the distance between tracks and light detectors, demonstrating enhanced uniformity of response for the anode-mounted PDS. We also show that xenon doping can substantially recover light losses due to contamination of the liquid argon by nitrogen

    Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

    Get PDF
    Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
    corecore