826 research outputs found

    Consequences of f(R)-theories of gravity on gravitational leptogenesis

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    f(R)-theories of gravity are reviewed in the framework of the matter-antimatter asymmetry in the Universe. The asymmetry is generated by the gravitational coupling of heavy (Majorana) neutrinos with the Ricci scalar curvature. In order that the mechanism works, a time varying non-zero Ricci curvature is necessary. The latter is provided by f(R) cosmology, whose Lagrangian density is of the form {\cal L}(R)\sim f(R). In particular we study the cases f(R)\sim R+\alpha R^n and f(R)\sim R^{1+\epsilon}.Comment: 14 page

    Cosmological evolution of thermal relic particles in f(R)f(R) gravity

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    By considering f(R)f(R) gravity models, the cosmic evolution is modified with respect to the standard Λ\LambdaCDM scenario. In particular, the thermal history of particles results modified. In this paper, we derive the evolution of relics particles (WIMPs) assuming a reliable f(R)f(R) cosmological solution and taking into account observational constraints. The connection to the PAMELA experiment is also discussed. Results are consistent with constraints coming from BICEP2 and PLANCK experiments.Comment: 8 pages, 4 figure

    Optimal discrimination between transient and permanent faults

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    An important practical problem in fault diagnosis is discriminating between permanent faults and transient faults. In many computer systems, the majority of errors are due to transient faults. Many heuristic methods have been used for discriminating between transient and permanent faults; however, we have found no previous work stating this decision problem in clear probabilistic terms. We present an optimal procedure for discriminating between transient and permanent faults, based on applying Bayesian inference to the observed events (correct and erroneous results). We describe how the assessed probability that a module is permanently faulty must vary with observed symptoms. We describe and demonstrate our proposed method on a simple application problem, building the appropriate equations and showing numerical examples. The method can be implemented as a run-time diagnosis algorithm at little computational cost; it can also be used to evaluate any heuristic diagnostic procedure by compariso

    Plant Metabolites. Structure and In Vitro Antiviral Activity of Quinovic Acid Glycosides from Uncaria tomentosa and Guettarda platyipoda

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    Abstract: A reinvestigation of the bark of Uncaria tommtosa afforded, in addition to the major quinovic acid glycosides 1-3, three further glycosides 4-6. The structures were elucidated by spectral and chemical studies. Furthermore, a series of antiviral tests were performed on all these glycosides and on the related glycosides 7-9, previously isolated from Guettarda platypoda

    1H, 13C and 15N assignment of the GNA1946 outer membrane lipoprotein from Neisseria meningitidis

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    GNA1946 (Genome-derived Neisseria Antigen 1946) is a highly conserved exposed outer membrane lipoprotein from Neisseria meningitidis bacteria of 287 amino acid length (31 kDa). Although the structure of NMB1946 has been solved recently by X-Ray crystallography, understanding the behaviour of GNA1946 in aqueuos solution is highly relevant for the discovery of the antigenic determinants of the protein that will possibly lead to a more efficient vaccine development against virulent serogroup B strain of N.meningitidis. Here we report almost complete 1H, 13C and 15N resonance assignments of GNA1946 (residues 10–287) in aqueous buffer solution

    Child Neurology: A Case Series of Heterogeneous Neuropsychiatric Symptoms and Outcome in Very Early-Onset Narcolepsy Type 1

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    Narcolepsy type 1 is a central disorder of hypersomnolence characterized by excessive daytime sleepiness, cataplexy (i.e., sudden loss of muscle tone during wakefulness triggered by emotions), and REM sleep-related manifestations that can present with a peculiar phenotype when arising at a pediatric age. Several features of childhood-onset narcolepsy type 1 are also common in neuropsychiatric conditions; discrete neuropsychiatric comorbidity has also been demonstrated. Here, we report on 3 children with very early narcolepsy type 1. All 3 patients had psychiatric features at the time of symptom onset coupled with peculiar motor disturbances. The course of narcolepsy symptoms also paralleled neuropsychiatric symptoms, suggesting a possible intrinsic link between sleep and psychological features. Multidisciplinary management is mandatory for pediatric narcolepsy type 1 since prompt disease management addressing neuropsychiatric symptoms could lead to better clinical outcomes and quality of life

    BEYOND WAIST CIRCUMFERENCE IN AN ADULT MALE POPULATION OF SOUTHERN ITALY: IS THERE ANY ROLE FOR SUBSCAPULAR SKINFOLD THICKNESS IN THE RELATIONSHIP BETWEEN INSULIN-LIKE GROWTH FACTOR-1 SYSTEM AND METABOLIC PARAMETERS ?

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    ABSTRACT Background: Apart from waist circumference, other adiposity measures, such as subscapular skin fold (SST), arouse growing interest due to their relationship to metabolic complications and cardiovascular risk. The Insulin-like Growth Factor (IGF)-1 system is deregulated in obese subjects in proportion to their degree of visceral adiposity. Aim : To examine the association among IGF-1, IGF-Binding Protein (BP)1 and 3 levels and different measures of adiposity in a sample of adult male population in Southern Italy. Materials and Methods: A complete database for this analysis was available for 229 (age range 50–82 years) participating at 2002-2004 Olivetti Heart Study follow-up. Results: After adjustment for age, IGF-1 was inversely associated with BMI and waist circumference (p<0.05). IGFBP1 was inversely associated with BMI, waist circumference, SST, Homeostasis Model Assessment (HOMA) index, Fat Mass (FM). HOMA index, age and SST significantly predicted the IGFBP1 plasma levels, with 24% of IGFPB-1 variability explained at a linear regression analysis. Conclusions: IGFBP1 inversely correlated to adiposity and HOMA index. Among adiposity indexes, SST was the best predictor of IGFPB-1 levels. The evaluation of some components of the IGFs system, and simple measures of body adiposity, such as SST, may represent a further tool to better evidence phenotype profiles associated to the pathogenetic mechanism of cardiovascular risk factor clustering in male adults

    Impact of COVID-19 pandemic lockdown on narcolepsy type 1 management

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    Study Objectives: Narcolepsy type 1 (NT1) is a chronic rare hypersomnia of central origin requiring a combination of behavioral and pharmacological treatments. During the coronavirus disease 2019 (COVID-19) pandemic, in Italy the population was forced into a lockdown. With this study, we aimed to describe the lockdown impact on NT1 symptom management, according to different patients' working schedule. Methods: In the period between 10 April and 15 May 2020, we performed routine follow-up visits by telephone (as recommended during the COVID-19 emergency) to 50 patients &gt;18&nbsp;years old (40% males) under stable long-term treatment. We divided patients into three groups: unchanged working schedule, forced working/studying at home, and those who lost their job (“lost occupation”). Current sleep–wake habit and symptom severity were compared with prelockdown assessment (six months before) in the three patient groups. Results: At assessment, 20, 22, and eight patients belonged to the unchanged, working/studying at home, and lost occupation groups, respectively. While in the lost occupation group, there were no significant differences compared with prepandemic assessment, the patients with unchanged schedules reported more nocturnal awakenings, and NT1 patients working/studying at home showed an extension of nocturnal sleep time, more frequent daytime napping, improvement of daytime sleepiness, and a significant increase in their body mass index. Sleep-related paralysis/hallucinations, automatic behaviors, cataplexy, and disturbed nocturnal sleep did not differ. Conclusions: Narcolepsy type 1 patients working/studying at home intensified behavioral interventions (increased nocturnal sleep time and daytime napping) and ameliorated daytime sleepiness despite presenting with a slight, but significant, increase of weight
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