379 research outputs found

    High-resolution Fourier-transform XUV photoabsorption spectroscopy of 14N15N

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    The first comprehensive high-resolution photoabsorption spectrum of 14N15N has been recorded using the Fourier-transform spectrometer attached to the Desirs beamline at the Soleil synchrotron. Observations are made in the extreme ultraviolet (XUV) and span 100,000-109,000 cm-1 (100-91.7 nm). The observed absorption lines have been assigned to 25 bands and reduced to a set of transition energies, f values, and linewidths. This analysis has verified the predictions of a theoretical model of N2 that simulates its photoabsorption and photodissociation cross section by solution of an isotopomer independent formulation of the coupled-channel Schroedinger equation. The mass dependence of predissociation linewidths and oscillator strengths is clearly evident and many local perturbations of transition energies, strengths, and widths within individual rotational series have been observed.Comment: 14 pages, 8 figures, one data archiv

    Otimização das temperaturas de anelamento de marcadores microssatĂ©lites Theobroma grandiflorum para caracterização de resistĂȘncia Ă  Moniliophthora perniciosa.

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    O objetivo desse trabalho foi identificar a temperatura Ăłtima para anelamento de cada primer microssatĂ©lite, desenvolvidos para trabalhos de biologia molecular com a espĂ©cie Theobroma grandiflorum, ligados a resistĂȘncia Ă  M. perniciosa

    Utilização de marcadores SSR de cupuaçuzeiro para identificação de QTL'S ligados Ă  resistĂȘncia a Moniliophthora perniciosa.

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    Dessa forma, o objetivo do trabalho foi identificar QTL's relacionados a resistĂȘncia do cupuaçuzeiro Ă  M. perniciosa, atravĂ©s da genotipagem de uma progĂȘnie contrastante entre os clones 174 ( susceptĂ­vel) x 1074 ( resistente)

    Morphological characteristics of motor neurons do not determine their relative susceptibility to degeneration in a mouse model of severe spinal muscular atrophy

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    Spinal muscular atrophy (SMA) is a leading genetic cause of infant mortality, resulting primarily from the degeneration and loss of lower motor neurons. Studies using mouse models of SMA have revealed widespread heterogeneity in the susceptibility of individual motor neurons to neurodegeneration, but the underlying reasons remain unclear. Data from related motor neuron diseases, such as amyotrophic lateral sclerosis (ALS), suggest that morphological properties of motor neurons may regulate susceptibility: in ALS larger motor units innervating fast-twitch muscles degenerate first. We therefore set out to determine whether intrinsic morphological characteristics of motor neurons influenced their relative vulnerability to SMA. Motor neuron vulnerability was mapped across 10 muscle groups in SMA mice. Neither the position of the muscle in the body, nor the fibre type of the muscle innervated, influenced susceptibility. Morphological properties of vulnerable and disease-resistant motor neurons were then determined from single motor units reconstructed in Thy.1-YFP-H mice. None of the parameters we investigated in healthy young adult mice - including motor unit size, motor unit arbor length, branching patterns, motor endplate size, developmental pruning and numbers of terminal Schwann cells at neuromuscular junctions - correlated with vulnerability. We conclude that morphological characteristics of motor neurons are not a major determinant of disease-susceptibility in SMA, in stark contrast to related forms of motor neuron disease such as ALS. This suggests that subtle molecular differences between motor neurons, or extrinsic factors arising from other cell types, are more likely to determine relative susceptibility in SMA

    Dual proteotoxic stress accelerates liver injury via activation of p62-Nrf2

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    Protein accumulation is the hallmark of various neuronal, muscular, and other human disorders. It is also often seen in the liver as a major protein-secretory organ. For example, aggregation of mutated alpha1-antitrypsin (AAT), referred to as PiZ, is a characteristic feature of AAT deficiency, whereas retention of hepatitis B surface protein (HBs) is found in chronic hepatitis B (CHB) infection. We investigated the interaction of both proteotoxic stresses in humans and mice. Animals overexpressing both PiZ and HBs (HBs-PiZ mice) had greater liver injury, steatosis, and fibrosis. Later they exhibited higher hepatocellular carcinoma load and a more aggressive tumor subtype. Although PiZ and HBs displayed differing solubility properties and distinct distribution patterns, HBs-PiZ animals manifested retention of AAT/HBs in the degradatory pathway and a marked accumulation of the autophagy adaptor p62. Isolation of p62-containing particles revealed retained HBs/AAT and the lipophagy adapter perilipin-2. p62 build-up led to activation of the p62–Nrf2 axis and emergence of reactive oxygen species. Our results demonstrate that the simultaneous presence of two prevalent proteotoxic stresses promotes the development of liver injury due to protein retention and activation of the p62–Nrf2 axis. In humans, the PiZ variant was over-represented in CHB patients with advanced liver fibrosis (unadjusted odds ratio = 9.92 [1.15–85.39]). Current siRNA approaches targeting HBs/AAT should be considered for these individuals. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland

    Automated Certification of Implicit Induction Proofs

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    International audienceTheorem proving is crucial for the formal validation of properties about user specifications. With the help of the Coq proof assistant, we show how to certify properties about conditional specifications that are proved using automated proof techniques like those employed by the Spike prover, a rewrite-based implicit induction proof system. The certification methodology is based on a new representation of the implicit induction proofs for which the underlying induction principle is an instance of Noetherian induction governed by an induction ordering over equalities. We propose improvements of the certification process and show that the certification time is reasonable even for industrial-size applications. As a case study, we automatically prove and certify more than 40% of the lemmas needed for the validation of a conformance algorithm for the ABR protocol

    Controlled production of atomic oxygen and nitrogen in a pulsed radio-frequency atmospheric-pressure plasma

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    International audienceRadio-frequency driven atmospheric pressure plasmas are efficient sources for the production of reactive species at ambient pressure and close to room temperature. Pulsing the radio-frequency power input provides additional control over species production and gas temperature. Here, we demonstrate the controlled production of highly reactive atomic oxygen and nitrogen in a pulsed radio-frequency ( ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn001.gif] 13.56 MHz) atmospheric-pressure plasma, operated with a small ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn002.gif] 0.1 % air-like admixture ( ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn003.gif] \rm N_2 / ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn004.gif] \rm O_2 at ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn005.gif] 4:1 ) through variations in the duty cycle. Absolute densities of atomic oxygen and nitrogen are determined through vacuum-ultraviolet absorption spectroscopy using the DESIRS beamline at the SOLEIL synchrotron coupled with a high resolution Fourier-transform spectrometer. The neutral-gas temperature is measured using nitrogen molecular optical emission spectroscopy. For a fixed applied-voltage amplitude (234?V), varying the pulse duty cycle from 10% to 100% at a fixed 10?kHz pulse frequency enables us to regulate the densities of atomic oxygen and nitrogen over the ranges of ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn006.gif] (0.18±0.03) ? ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn007.gif] (3.7±0.1)× 10^20 ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn008.gif] \rm m^-3 and ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn009.gif] (0.2±0.06) ? ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn010.gif] (4.4±0.8) × 10^19 ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn011.gif] \rm m^-3 , respectively. The corresponding 11?K increase in the neutral-gas temperature with increased duty cycle, up to a maximum of ##IMG## [http://ej.iop.org/images/0022-3727/50/45/455204/daa8da2ieqn012.gif] (314±4) K, is relatively small. This additional degree of control, achieved through regulation of the pulse duty cycle and time-averaged power, could be of particular interest for prospective biomedical applications

    The effect of mirabegron on energy expenditure and brown adipose tissue in healthy lean South Asian and Europid men

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    Aim: To compare the effects of cold exposure and the ÎČ3-adrenergic receptor agonist mirabegron on plasma lipids, energy expenditure and brown adipose tissue (BAT) activity in South Asians versus Europids. Materials and Methods: Ten lean Dutch South Asian (aged 18-30 years; body mass index [BMI] 18-25 kg/m2 ) and 10 age- and BMI-matched Europid men participated in a randomized, double-blinded, cross-over study consisting of three interventions: short-term (~ 2 hours) cold exposure, mirabegron (200 mg one dose p.o.) and placebo. Before and after each intervention, we performed lipidomic analysis in serum, assessed resting energy expenditure (REE) and skin temperature, and measured BAT fat fraction by magnetic resonance imaging. Results: In both ethnicities, cold exposure increased the levels of several serum lipid species, whereas mirabegron only increased free fatty acids. Cold exposure increased lipid oxidation in both ethnicities, while mirabegron increased lipid oxidation in Europids only. Cold exposure and mirabegron enhanced supraclavicular skin temperature in both ethnicities. Cold exposure decreased BAT fat fraction in both ethnicities. After the combination of data from both ethnicities, mirabegron decreased BAT fat fraction compared with placebo. Conclusions: In South Asians and Europids, cold exposure and mirabegron induced beneficial metabolic effects. When combining both ethnicities, cold exposure and mirabegron increased REE and lipid oxidation, coinciding with a higher supraclavicular skin temperature and lower BAT fat fraction.Diabetes Research Foundation Fellowship 2015.81.1808Netherlands CardioVascular Research Initiative: 'the Dutch Heart Foundation, Dutch Federation of University Medical Centers, the Netherlands Organisation for Health Research and Development and the Royal Netherlands Academy of Sciences' CVON2014-02 ENERGISE CVON2017-20 GENIUS-IIEuropean Union (EU) 602485European Research Council (NOMA-MRI) PCNR is an Established Investigator of the Netherlands Heart Foundation 2009T03

    To investigate relative effectiveness of the dimensions of interactivity

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    This thesis is about interactivity. It is about the dimensions of interactive communication which have become a major element of contemporary marketing practice. The concept of interactivity has been explored in the fields of advertising research, and communication and media studies. However, there is an overall absence of any published work concerning research into the dimensions of interactivity, in the marketing domain. This thesis seeks to correct this situation and investigates the relative effectiveness of the dimensions of interactivity, set in the context of travel weblogs. The aim is to determine how three principal dimensions of interactivity namely, active control, two-way communication, and real-time communication, affects users‟ attitudes and usage intentions. This thesis also examines the effect of motive factors, such as social interaction, information of travel weblogs, and enjoyment, upon a user‟s attitudes and usage intentions. The relationships among these variables are examined within a research framework provided by this study. Data was collected through an online questionnaire and semi-structured interviews. The findings verify that the dimensions of interactivity and motivation factors can have positive influence upon users‟ attitudes and usage intentions.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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