67 research outputs found

    Runtime support for stencil data-parallel applications on multicore architectures

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    In the field of structured parallel programming we study and implement a shared-memory runtime support for stencil data-parallel applications expressed according to the virtual processor formalism. It is a novel approach to introduce some optimizations that cannot be provided at compile time. The effectiveness of our runtime support is then evaluated with respect to optimized hand-written data-parallel applications

    How does dark matter affect compact star properties and high density constraints of strongly interacting matter

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    We study the impact of asymmetric bosonic dark matter on neutron starproperties, including possible changes of tidal deformability, maximum mass,radius, and matter distribution inside the star. The conditions at which darkmatter particles tend to condensate in the star's core or create an extendedhalo are presented. We show that dark matter condensed in a core leads to adecrease of the total gravitational mass and tidal deformability compared to apure baryonic star, which we will perceive as an effective softening of theequation of state. On the other hand, the presence of a dark matter haloincreases those observable quantities. Thus, observational data on compactstars could be affected by accumulated dark matter and, consequently,constraints we put on strongly interacting matter at high densities. To confirmthe presence of dark matter in the compact star's interior, and to break thedegeneracy between the effect of accumulated dark matter and stronglyinteracting matter properties at high densities, several astrophysical and GWtests are proposed.<br

    The effects of self-interacting bosonic dark matter on neutron star properties

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    We propose a model of asymmetric bosonic dark matter (DM) with self-repulsion mediated by the vector field coupled to the complex scalar particles. By adopting the two-fluid formalism, we study different DM distribution regimes, either, fully condensed inside the core of a star or, otherwise, distributed in a dilute halo around a neutron star (NS). We show that DM condensed in a core leads to a decrease of the total gravitational mass, radius and tidal deformability compared to a pure baryonic star with the same central density, which we will perceive as an effective softening of the equation of state (EoS). On the other hand, the presence of a DM halo increases the tidal deformability and total gravitational mass. As a result, an accumulated DM inside compact stars could mimic an apparent stiffening of strongly interacting matter equation of state and constraints we impose on it at high densities. From the performed analysis of the effect of DM particles in a MeV-GeV mass-scale, interaction strength, and relative DM fractions inside NSs we obtained a rigorous constraint on model parameters. Finally, we discuss several smoking guns of the presence of DM that are free from the above mentioned apparent modification of the strongly interacting matter equation of state. With this we could be probed with the future astrophysical and gravitational wave (GW) surveys.Comment: 14 pages, 5 figure

    What is the nature of the HESS J1731-347 compact object?

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    Once further confirmed in future analyses, the radius and mass measurement of HESS J1731-347 with M=0.77−0.17+0.20 M⊙M=0.77^{+0.20}_{-0.17}~M_{\odot} and R=10.4−0.78+0.86 kmR=10.4^{+0.86}_{-0.78}~\rm km will be among the lightest and smallest compact objects ever detected. This raises many questions about its nature and opens up the window for different theories to explain such a measurement. In this article, we use the information from Doroshenko et al. (2022) on the mass, radius, and surface temperature together with the multimessenger observations of neutron stars to investigate the possibility that HESS J1731-347 is one of the lightest observed neutron star, a strange quark star, a hybrid star with an early deconfinement phase transition, or a dark matter-admixed neutron star. The nucleonic and quark matter are modeled within realistic equation of states (EOSs) with a self-consistent calculation of the pairing gaps in quark matter. By performing the joint analysis of the thermal evolution and mass-radius constraint, we find evidence that within a 1σ\sigma confidence level, HESS J1731-347 is consistent with the neutron star scenario with the soft EOS as well as with a strange and hybrid star with the early deconfinement phase transition with a strong quark pairing and neutron star admixed with dark matter.Comment: 9 pages, 3 figure

    Adherence to Mediterranean Diet Measured through Medi-Lite Score and Obesity: A Retrospective Study

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    We recently developed and validated a questionnaire to measure adherence to the Mediterranean diet, called Medi-Lite. The aim of this study was to assess the accuracy of the Medi-Lite adherence score in relation to obesity status. A total of 208 patients who attended the Clinical Nutrition Unit of Careggi University Hospital, Florence, were included in this retrospective analysis. Of them, 126 (45%) had abdominal obesity (110 F; 16 M). The mean adherence score, calculated through the Medi-Lite questionnaire, was 9.5 ± 2.2, with significantly (p p p 9

    Nutritional Interventions in the Management of Fibromyalgia Syndrome

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    Fibromyalgia (FM) is a multifactorial syndrome of unknown etiology, characterized by widespread chronic pain and various somatic and psychological manifestations. The management of FM requires a multidisciplinary approach combining both pharmacological and nonpharmacological strategies. Among nonpharmacological strategies, growing evidence suggests a potential beneficial role for nutrition. This review summarizes the possible relationship between FM and nutrition, exploring the available evidence on the effect of dietary supplements and dietary interventions in these patients. Analysis of the literature has shown that the role of dietary supplements remains controversial, although clinical trials with vitamin D, magnesium, iron and probiotics&rsquo; supplementation show promising results. With regard to dietary interventions, the administration of olive oil, the replacement diet with ancient grains, low-calorie diets, the low FODMAPs diet, the gluten-free diet, the monosodium glutamate and aspartame-free diet, vegetarian diets as well as the Mediterranean diet all appear to be effective in reducing the FM symptoms. These results may suggest that weight loss, together with the psychosomatic component of the disease, should be taken into account. Therefore, although dietary aspects appear to be a promising complementary approach to the treatment of FM, further research is needed to provide the most effective strategies for the management of FM

    Spritz: General Relativistic Magnetohydrodynamics with Neutrinos

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    We here present a new version of the publicly available general relativistic magnetohydrodynamic (GRMHD) code Spritz\texttt{Spritz}, which now includes an approximate neutrino leakage scheme able to handle neutrino cooling and heating. The leakage scheme is based on the publicly available ZelmaniLeak\texttt{ZelmaniLeak} code, with a few modifications in order to properly work with Spritz\texttt{Spritz}. We discuss the involved equations, physical assumptions, and implemented numerical methods, along with a large battery of general relativistic tests performed with and without magnetic fields. Our tests demonstrate the correct implementation of the neutrino leakage scheme, paving the way for further improvements of our neutrino treatment and the first application to magnetized binary neutron star mergers. We also discuss the implementation in the Spritz\texttt{Spritz} code of high-order methods for a more accurate evolution of hydrodynamical quantities.Comment: 34 pages, 16 figures. The code is available on Zenodo as version 1.1.0 at https://doi.org/10.5281/zenodo.3689751. Initial data and equation of state used in this paper can be downloaded from https://drive.google.com/drive/folders/1kGBRW_AhKjHrOi76uXXPRyaCc1BfgqQN?usp=sharin

    Effects of vegetarian versus Mediterranean diet on kidney function: Findings from the CARDIVEG study

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    BACKGROUND: The aim of the present study was to assess the effects of a lacto‐ovo‐vegetarian diet (VD), compared to a Mediterranean diet (MD), on kidney function in a group of subjects with medium‐to‐low cardiovascular risk profile. METHODS: We analysed 107 subjects (82 women, 25 men; median age 52) who followed a VD (n = 54) and a MD (n = 53) for 3 months in the CARDIVEG study, a randomized, open, crossover trial that compared the effects of these 2 diets on cardiovascular disease risk. RESULTS: The effect of the two diets on kidney function markers was evaluated by conducting a general linear model for repeated measurements adjusted for possible confounding factors such as age, sex, physical activity, alcohol, smoking, hypertension, LDL cholesterol, glucose and body weight change. A significant reduction in creatinine (−5.3%; P < .001), urea nitrogen levels (−9%; P = .001), blood urea nitrogen (BUN) (−8.7%; P = .001) and BUN/creatinine ratio (−5.8%; P < .001), and an increase in estimated glomerular filtration rate (eGFR) (+3.5%; P = .001) was observed during the VD period. On the contrary, no significant changes were noted in the MD group. Variations obtained in the two dietary interventions were significantly different (P < .0001) for creatinine levels, BUN/creatinine and eGFR, for which opposite trends were observed in the VD and MD groups. CONCLUSIONS: In a selected group of subjects with medium‐to‐low cardiovascular risk profile, a 3 month VD period determined significant improvements in kidney function markers. Further trials are needed to confirm these results

    How does dark matter affect compact star properties and high density constraints of strongly interacting matter

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    We study the impact of asymmetric bosonic dark matter on neutron star properties, including possible changes of tidal deformability, maximum mass, radius, and matter distribution inside the star. The conditions at which dark matter particles tend to condensate in the star’s core or create an extended halo are presented. We show that dark matter condensed in a core leads to a decrease of the total gravitational mass and tidal deformability compared to a pure baryonic star, which we will perceive as an effective softening of the equation of state. On the other hand, the presence of a dark matter halo increases those observable quantities. Thus, observational data on compact stars could be affected by accumulated dark matter and, consequently, constraints we put on strongly interacting matter at high densities. To confirm the presence of dark matter in the compact star’s interior, and to break the degeneracy between the effect of accumulated dark matter and strongly interacting matter properties at high densities, several astrophysical and GW tests are proposed

    Influence of Functional Bio-Based Coatings Including Chitin Nanofibrils or Polyphenols on Mechanical Properties of Paper Tissues

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    The paper tissue industry is a constantly evolving sector that supplies markets that require products with different specific properties. In order to meet the demand of functional properties, ensuring a green approach at the same time, research on bio-coatings has been very active in recent decades. The attention dedicated to research on functional properties has not been given to the study of the morphological and mechanical properties of the final products. This paper studied the effect of two representative bio-based coatings on paper tissue. Coatings based on chitin nanofibrils or polyphenols were sprayed on paper tissues to provide them, respectively, with antibacterial and antioxidant activity. The chemical structure of the obtained samples was preliminarily compared by ATR-FTIR before and after their application. Coatings were applied on paper tissues and, after drying, their homogeneity was investigated by ATR-FTIR on different surface areas. Antimicrobial and antioxidant properties were found for chitin nanofibrils- and polyphenols-treated paper tissues, respectively. The mechanical properties of treated and untreated paper tissues were studied, considering as a reference the same tissue paper sample treated only with water. Different mechanical tests were performed on tissues, including penetration, tensile, and tearing tests in two perpendicular directions, to consider the anisotropy of the produced tissues for industrial applications. The morphology of uncoated and coated paper tissues was analysed by field emission scanning electron microscopy. Results from mechanical properties evidenced a correlation between morphological and mechanical changes. The addition of polyphenols resulted in a reduction in mechanical resistance, while the addition of chitin enhanced this property. This study evidenced the different effects produced by two novel coatings on paper tissues for personal care in terms of properties and structure.This research was funded by the Bio-Based Industries Joint Undertaking under the European Union Horizon 2020 research program (BBI-H2020), ECOFUNCO project, grant number G.A 837863
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