Search results for "Fermi"
showing 10 items of 1388 documents
Mixed topological semimetals driven by orbital complexity in two-dimensional ferromagnets
2018
The concepts of Weyl fermions and topological semimetals emerging in three-dimensional momentum space are extensively explored owing to the vast variety of exotic properties that they give rise to. On the other hand, very little is known about semimetallic states emerging in two-dimensional magnetic materials, which present the foundation for both present and future information technology. Here, we demonstrate that including the magnetization direction into the topological analysis allows for a natural classification of topological semimetallic states that manifest in two-dimensional ferromagnets as a result of the interplay between spin-orbit and exchange interactions. We explore the emerg…
Phase stability and electronic structure of iridium metal at the megabar range
2019
[EN] The 5d transition metals have attracted specific interest for high-pressure studies due to their extraordinary stability and intriguing electronic properties. In particular, iridium metal has been proposed to exhibit a recently discovered pressure-induced electronic transition, the so-called core-level crossing transition at the lowest pressure among all the 5d transition metals. Here, we report an experimental structural characterization of iridium by x-ray probes sensitive to both long- and short-range order in matter. Synchrotron-based powder x-ray diffraction results highlight a large stability range (up to 1.4 Mbar) of the low-pressure phase. The compressibility behaviour was char…
Uhlmann number in translational invariant systems
2019
We define the Uhlmann number as an extension of the Chern number, and we use this quantity to describe the topology of 2D translational invariant Fermionic systems at finite temperature. We consider two paradigmatic systems and we study the changes in their topology through the Uhlmann number. Through the linear response theory we linked two geometrical quantities of the system, the mean Uhlmann curvature and the Uhlmann number, to directly measurable physical quantities, i.e. the dynamical susceptibility and to the dynamical conductivity, respectively.
Phase separations induced by a trapping potential in one-dimensional fermionic systems as a source of core-shell structures
2018
Ultracold fermionic gases in optical lattices give a great opportunity for creating different types of novel states. One of them is phase separation induced by a trapping potential between different types of superfluid phases. The core-shell structures, occurring in systems with a trapping potential, are a good example of such separations. The types and the sequences of phases which emerge in such structures can depend on spin-imbalance, shape of the trap and on-site interaction strength. In this work, we investigate the properties of such structures within an attractive Fermi gas loaded in the optical lattice, in the presence of the trapping potential and their relations to the phase diagr…
The Daily Consumption of Cola Can Determine Hypocalcemia: A Case Report of Postsurgical Hypoparathyroidism-Related Hypocalcemia Refractory to Supplem…
2017
The consumption of soft drinks is a crucial factor in determining persistent hypocalcemia. The aim of the study was to evaluate the biochemical mechanisms inducing hypocalcemia in a female patient with usual high consumption of cola drink and persistent hypocalcemia, who failed to respond to high doses of calcium and calcitriol supplementation. At baseline and after pentagastrin injection, gastric and duodenal secretion samples were collected and calcium and total phosphorus concentrations were evaluated. At the same time, blood calcium, total phosphorus, sodium, potassium, chloride, magnesium concentrations and vitamin D were sampled. After intake of cola (1 L) over 180 min, gastric and du…
Transcranial random noise stimulation over the primary motor cortex in PD-MCI patients: a crossover, randomized, sham-controlled study
2020
AbstractMild cognitive impairment (MCI) is a very common non-motor feature of Parkinson’s disease (PD) and the non-amnestic single-domain is the most frequent subtype. Transcranial random noise stimulation (tRNS) is a non-invasive technique, which is capable of enhancing cortical excitability. As the main contributor to voluntary movement control, the primary motor cortex (M1) has been recently reported to be involved in higher cognitive functioning. The aim of this study is to evaluate the effects of tRNS applied over M1 in PD-MCI patients in cognitive and motor tasks. Ten PD-MCI patients, diagnosed according to the Movement Disorder Society, Level II criteria for MCI, underwent active (re…
Cognitive functioning throughout adulthood and illness stages in individuals with psychotic disorders and their unaffected siblings
2021
The European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-2010-241909 (EUGEI); The Spanish sample was supported by the Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III (SAM16PE07CP1, PI16/02012, PI19/024) (...)
Pain Education in Schools of Nursing: a Survey of the Italian Academic Situation.
2018
Introduction: Proper assessment of pain is imperative for the development of an effective pain management plan and is a core responsibility of nurses and healthcare professionals. This article describes the contents of Italian on-line bachelor's in nursing degree programs, with particular focus on pain management.Method: A descriptive study was made on curricula published and available on-line in Italian Nursing Schools, and the concordance with the standards set by the Consensus Curriculum on Pain for Nursing ofthe International Association for the Study of Pain (IASP, 2015) was analyzed.Results: Of all the bachelor programs published on-line, 42.6% offered programs and courses specificall…
A computational approach for the assessment of executive functions in patients with obsessive-compulsive disorder
2019
Previous studies on obsessive–compulsive disorder (OCD) showed impairments in executive domains, particularly in cognitive inhibition. In this perspective, the use of virtual reality showed huge potential in the assessment of executive functions; however, unfortunately, to date, no study on the assessment of these patients took advantage of the use of virtual environments. One of the main problems faced within assessment protocols is the use of a limited number of variables and tools when tailoring a personalized program. The main aim of this study was to provide a heuristic decision tree for the future development of tailored assessment protocols. To this purpose, we conducted a study that…
Metacognitive Therapy in Patients with Tinnitus: a Single Group Study
2019
Tinnitus is often in comorbidity with anxiety and depression, and several authors have proposed a reduced efficiency of the top-down executive control in its perception. This single-group study describes a novel application of the metacognitive therapy (MCT), which works on a top-down engagement of proactive attentional control mechanisms on a group of patients with tinnitus, to see its impact on the perception of tinnitus and its anxiety and depression correlates. Eight metacognitive therapy group-sessions were proposed to a group of nine patients, as part of a regional project conducted at the University General Hospital “Paolo Giaccone” of Palermo. The last was a follow-up session, propo…