685 research outputs found

    Contribution of the institutions in the Northern region of Brazil to the development of plant cultivars and their impact on agriculture

    Get PDF
    This paper describes the development of breeding programs in northern Brazil and their main impacts on agriculture. Their contribution to the breeding of the species palm oil, acai fruit, cacao, cupuaçu, guarana, tomato, camu-camu, cocona, peach palm, and rubber was laid out in detail. Advances in breeding programs of institutions such as Embrapa, Ceplac, Inpa, and Universities require investments in infrastructure and in human and financial resources to ensure continuity and efficiency in economic, social and environmental gains. The improvement of native species, the main focus of the breeding programs of the institutions in the Northern region of Brazil, is a form of exploiting the Amazonian biodiversity for the benefit of society. Therefore, policies to foster research institutions should be a subject of deliberation and action of the scientific and technological community in Brazil

    Necessidade ou oportunidade? Os dilemas dos microempreendedores fluminenses: Need or opportunity? The dilemmas of rio's microentrepreneurs

    Get PDF
    O ambiente de negócios no Brasil é hostil. A carga tributária é elevada, a inflação é elevada, os juros são os mais altos no mundo. Por anos, vivemos uma crise financeira interminável, resultando em níveis alarmantes de desemprego. A situação piorou ainda mais durante a pandemia do Covid-19. Diante das normas de isolamento e quarentena para conter a propagação do coronavírus, muitos empreendedores precisaram interromper suas operações e demitir funcionários. Escolas fecharam. Restaurantes fecharam. Seu Manoel foi um dos trabalhadores demitidos durante a pandemia. Ele representava a única fonte de renda da família. “E agora, o que vou fazer?”, pensou Manoel após receber de seu chefe a carta de demissão. Uma recolocação profissional seria inviável por conta da idade avançada e por conta dos índices cada vez maiores de desemprego no país. Então, diante da necessidade de arcar com as despesas básicas da família, Manoel tornou-se microempreendor individual. Mesmo sem nenhuma experiência ou formação empresarial, ele iniciou um negócio no ramo de alimentação. “Posso não ter formação, mas tenho fé e muita disposição. Minha família depende de mim!”, foram as primeiras palavras ditas por Manoel no dia da inauguração do seu novo negócio

    A ordem dos exercícios de força mono ou multiarticulares influencia o volume de treinamento? / Does the order of single- or multi-joint resistance exercises influence training volume?

    Get PDF
    O treinamento de força (TF) é um importante componente de programas de exercícios, atuando na promoção de melhoras consideráveis em parâmetros ligados a performance esportiva, estética corporal e na prevenção/tratamento de diversas doenças. O objetivo do presente estudo foi comparar a carga total levantada realizada entre quatro sessões de TF de corpo todo diferindo quanto à ordem dos exercícios. Doze homens hígidos com experiência prévia no TF (Idade: 30,9±1,8 anos; Massa corporal total: 87,2±3,4 kg; Estatura: 177±0,07 cm; Experiência com TF: 3,1±1,4 anos; Força relativa no exercício supino reto: 1,2±0,12; Força relativa no exercício meio-agachamento: 1,5±0,09). Os participantes foram aleatoriamente submetidos a 4 sessões com diferentes ordens de exercícios, separadas por um período de 72 horas cada. Para cada exercício, os participantes realizavam 4 séries até o ponto de falha muscular concêntrica sob carga de 10RM. Durante cada sessão de TF, foram contabilizados a carga utilizada em cada série para cálculo posterior da carga total levantada (CTL). Não foram observadas diferenças significantes entre as sessões para a CTL (p>0,05). Conclui-se que, diferentes ordens dos exercícios de força não influenciam na CTL. Dessa forma, preferências pessoais, assim como a disponibilidade momentânea dos implementos e os objetivos do praticante, devem ser levadas em consideração pelos treinadores quando da prescrição do treinamento de força.

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

    Get PDF
    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

    Get PDF
    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

    Get PDF
    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

    Get PDF
    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

    Get PDF
    Peer reviewe

    Measurements of Higgs boson production cross sections and couplings in the diphoton decay channel at root s=13 TeV

    Get PDF
    Measurements of Higgs boson production cross sections and couplings in events where the Higgs boson decays into a pair of photons are reported. Events are selected from a sample of proton-proton collisions at root s = 13TeV collected by the CMS detector at the LHC from 2016 to 2018, corresponding to an integrated luminosity of 137 fb(-1). Analysis categories enriched in Higgs boson events produced via gluon fusion, vector boson fusion, vector boson associated production, and production associated with top quarks are constructed. The total Higgs boson signal strength, relative to the standard model (SM) prediction, is measured to be 1.12 +/- 0.09. Other properties of the Higgs boson are measured, including SM signal strength modifiers, production cross sections, and its couplings to other particles. These include the most precise measurements of gluon fusion and vector boson fusion Higgs boson production in several different kinematic regions, the first measurement of Higgs boson production in association with a top quark pair in five regions of the Higgs boson transverse momentum, and an upper limit on the rate of Higgs boson production in association with a single top quark. All results are found to be in agreement with the SM expectations.Peer reviewe

    Observation of tW production in the single-lepton channel in pp collisions at root s=13 TeV

    Get PDF
    A measurement of the cross section of the associated production of a single top quark and a W boson in final states with a muon or electron and jets in proton-proton collisions at root s = 13 TeV is presented. The data correspond to an integrated luminosity of 36 fb(-1) collected with the CMS detector at the CERN LHC in 2016. A boosted decision tree is used to separate the tW signal from the dominant t (t) over bar background, whilst the subleading W+jets and multijet backgrounds are constrained using data-based estimates. This result is the first observation of the tW process in final states containing a muon or electron and jets, with a significance exceeding 5 standard deviations. The cross section is determined to be 89 +/- 4 (stat) +/- 12 (syst) pb, consistent with the standard model.Peer reviewe
    corecore