707 research outputs found

    On the structure of Borel stable abelian subalgebras in infinitesimal symmetric spaces

    Full text link
    Let g=g_0+g_1 be a Z_2-graded Lie algebra. We study the posets of abelian subalgebras of g_1 which are stable w.r.t. a Borel subalgebra of g_0. In particular, we find out a natural parametrization of maximal elements and dimension formulas for them. We recover as special cases several results of Kostant, Panyushev, Suter.Comment: Latex file, 35 pages, minor corrections, some examples added. To appear in Selecta Mathematic

    Changes in sleep pattern, sense of time and digital media use during COVID-19 lockdown in Italy

    Get PDF
    Italy is one of the major COVID-19 hotspots. To reduce the spread of the infections and the pressure on Italian healthcare systems, since March 10, 2020, Italy has been under a total lockdown, forcing people into home confinement. Here we present data from 1,310 people living in the Italian territory (Mage = 23.91 ± 3.60 years, 880 females, 501 workers, 809 university students), who completed an online survey from March 24 to March 28, 2020. In the survey, we asked participants to think about their use of digital media before going to bed, their sleep pattern and their subjective experience of time in the previous week (March 17–23, which was the second week of the lockdown) and up to the first week of February (February 3–10, before any restriction in any Italian area). During the lockdown, people increased the usage of digital media near bedtime, but this change did not affect sleep habits. Nevertheless, during home confinement, sleep timing markedly changed, with people going to bed and waking up later, and spending more time in bed, but, paradoxically, also reporting a lower sleep quality. The increase in sleep difficulties was stronger for people with a higher level of depression, anxiety and stress symptomatology, and associated with the feeling of elongation of time. Considering that the lockdown is likely to continue for weeks, research data are urgently needed to support decision making, to build public awareness and to provide timely and supportive psychosocial interventions

    The interplay between mothers\u2019 and children behavioral and psychological factors during COVID-19: an Italian study

    Get PDF
    Italy has been the first nation outside of Asia to face the COVID-19 outbreak. To limit viral transmission of infection, by March 10th, 2020, the Italian Government has ordered a national lockdown, which established home confinement, home (smart) working, and temporary closure of non-essential businesses and schools. The present study investigated how these restrictive measures impacted mothers and their pre-school children\u2019s behavioral habits (i.e., sleep timing and quality, subjective time experience) and psychological well-being (i.e., emotion regulation, self-regulation capacity). An online survey was administered to 245 mothers with pre-school children (from 2 to 5\ua0years). Mothers were asked to fill the survey thinking both on their habits, behaviors, and emotions and on those of their children during the quarantine, and retrospectively, before the national lockdown (i.e., in late February). A general worsening of sleep quality and distortion of time experience in both mothers and children, as well as increasing emotional symptoms and self-regulation difficulties in children, was observed. Moreover, even when the interplay between the behavioral and psychological factors was investigated, the factor that seems to mostly impact both mothers' and children's psychological well-being was their sleep quality. Overall, central institutions urgently need to implementing special programs for families, including not only psychological support to sustain families with working parents and ameliorating children's management

    Chronic Central Serous Chorioretinopathy with Pigment Epithelium Detachment Treated with Sildenafil: A Case Report

    Get PDF
    Central serous chorioretinopathy (CSCR) is a retinal disease that may be complicated by the development of serous retinal pigment epithelial detachment (PED). The exact molecular mechanisms of CSCR have remained uncertain as well as there is no effective medical therapy. Herein, we describe a case of a 43-year-old male suffering from chronic CSCR with PED and visual acuity reduction (20/40) that showed improvement in visual acuity (20/25) and metamorphopsia 2 weeks after daily intake of 20 mg sildenafil tablets. Optical coherence tomography (OCT) scan showed resolution of PED with residual degeneration of the photoreceptor inner and outer segment layer and retinal pigmented epithelium. The patient continued treatment with sildenafil 20 mg for 2 months. Six months after the discontinuation of therapy, visual acuity was maintained, with absence of PED at OCT. Our case supports the hypothesis that phosphodiesterase type 5 (PDE-5) inhibitors may be an alternative in the treatment of patients with CSCR, alone or combined with other medications

    Wearable Sleep Technology in Clinical and Research Settings

    Get PDF
    The accurate assessment of sleep is critical to better understand and evaluate its role in health and disease. The boom in wearable technology is part of the digital health revolution and is producing many novel, highly sophisticated and relatively inexpensive consumer devices collecting data from multiple sensors and claiming to extract information about users' behaviors, including sleep. These devices are now able to capture different biosignals for determining, for example, HR and its variability, skin conductance, and temperature, in addition to activity. They perform 24/7, generating overwhelmingly large data sets (big data), with the potential of offering an unprecedented window on users' health. Unfortunately, little guidance exists within and outside the scientific sleep community for their use, leading to confusion and controversy about their validity and application. The current state-of-the-art review aims to highlight use, validation and utility of consumer wearable sleep-trackers in clinical practice and research. Guidelines for a standardized assessment of device performance is deemed necessary, and several critical factors (proprietary algorithms, device malfunction, firmware updates) need to be considered before using these devices in clinical and sleep research protocols. Ultimately, wearable sleep technology holds promise for advancing understanding of sleep health; however, a careful path forward needs to be navigated, understanding the benefits and pitfalls of this technology as applied in sleep research and clinical sleep medicine

    Moral reasoning behind the veil of ignorance: An investigation into perspective-taking accessibility in the context of autonomous vehicles

    Get PDF
    Perspective-taking (PT) accessibility has been recognized as an important factor in affecting moral reasoning, also playing a non-trivial role in moral investigation towards autonomous vehicles (AVs). A new proposal to deepen this effect leverages the principles of the veil of ignorance (VOI), as a moral reasoning device aimed to control self-interested decisions by limiting the access to specific perspectives and to potentially biased information. Throughout two studies, we deepen the role of VOI reasoning in the moral perception of AVs, disclosing personal and contingent information progressively throughout the experiment. With the use of the moral trilemma paradigm, two different VOI conditions were operationalized, inspired by the Original Position theory by John Rawls and the Equiprobability Model by John Harsanyi. Evidence suggests a significant role of VOI reasoning in affecting moral reasoning, which seems not independent from the order in which information is revealed. Coherently, a detrimental effect of self-involvement on utilitarian behaviours was detected. These results highlight the importance of considering PT accessibility and self-involvement when investigating moral attitudes towards AVs, since it can help the intelligibility of general concerns and hesitations towards this new technology

    Root polytopes and abelian ideals

    Full text link
    We study the root polytope PΦ\mathcal P_\Phi of a finite irreducible crystallographic root system Φ\Phi using its relation with the abelian ideals of a Borel subalgebra of a simple Lie algebra with root system Φ\Phi. We determine the hyperplane arrangement corresponding to the faces of codimension 2 of PΦ\mathcal P_\Phi and analyze its relation with the facets of PΦ\mathcal P_\Phi. For Φ\Phi of type AnA_n or CnC_n, we show that the orbits of some special subsets of abelian ideals under the action of the Weyl group parametrize a triangulation of PΦ\mathcal P_\Phi. We show that this triangulation restricts to a triangulation of the positive root polytope PΦ+\mathcal P_\Phi^+.Comment: 41 pages, revised version, accepted for publication in Journal of Algebraic Combinatoric

    A synthetic cytokinin primes photosynthetic and growth response in grapevine under ion-independent salinity stress

    Get PDF
    Aiding optimal plant–environment interaction would favor plant resilience against environmental constrains including salt stress. We test the hypothesis that 6-Benzylaminopurine (BAP) primes grapevine’s salt tolerance in vines (Vitis vinifera) received salt water (NaCl 100 mM) through the modulation of gene expression of BAP (AHK4, AHP1) and salt-stress (CAT, APX) inducible genes and morpho-physiological traits. A subgroup of vines had previously (48 h) been primed with BAP (80 mg/L) before salt stress. The gene expressions were 30% (CAT) and 56% (APX) lower in primed salt-stressed vines than that in un-primed. Salt treatment did not increase leaf Na+ but it lowered stomatal conductance (g s), photosynthesis (A), stem water potential (less negative) and photosystem-II efficiency (F v/F m). Chlorophyll-a concentrations were 30% higher in BAP-primed compared to un-primed. Adverse effects of salt were significantly reduced, maintaining high A/g s, F v/F m and growth. After the relief of the stress, the BAP primed vines had a fast recovery
    • …
    corecore