6,258 research outputs found
Quantum control and long-range quantum correlations in dynamical Casimir arrays
The recent observation of the dynamical Casimir effect in a modulated
superconducting waveguide, coronating thirty years of world-wide research,
empowered the quantum technology community with a powerful tool to create
entangled photons on-chip. In this work we show how, going beyond the single
waveguide paradigm using a scalable array, it is possible to create
multipartite nonclassical states, with the possibility to control the
long-range quantum correlations of the emitted photons. In particular, our
finite-temperature theory shows how maximally entangled states can be
engineered in a realistic setup. The results here presented open the way to new
kinds of quantum fluids of light, arising from modulated vacuum fluctuations in
linear systems
Cranial neuralgias: from physiopathology to pharmacological treatment
Cranial neuralgias are paroxysmal painful disorders of the head characterised by some shared features such as unilaterality of symptoms, transience and recurrence of attacks, superficial and "shock-like" quality of pain and the presence of triggering factors. Although rare, these disorders must be promptly recognised as they harbour a relatively high risk for underlying compressive or inflammatory disease. Nevertheless, misdiagnosis is frequent. Trigeminal and glossopharyngeal neuralgias are sustained in most cases by a neurovascular conflict in the posterior fossa resulting in a hyperexcitability state of the trigeminal circuitry. If the aetiology of trigeminal neuralgia (TN) and other typical neuralgias must be brought back to the peripheral injury, their pathogenesis could involve central allodynic mechanisms, which, in patients with inter-critical pain, also engage the nociceptive neurons at the thalamic-cortical level. Currently available medical treatments for TN and other cranial neuralgias are reviewed
A description of the Galactic Center excess in the Minimal Supersymmetric Standard Model
Observations with the Fermi Large Area Telescope (LAT) indicate an excess in
gamma rays originating from the center of our Galaxy. A possible explanation
for this excess is the annihilation of Dark Matter particles. We have
investigated the annihilation of neutralinos as Dark Matter candidates within
the phenomenological Minimal Supersymmetric Standard Model (pMSSM). An
iterative particle filter approach was used to search for solutions within the
pMSSM. We found solutions that are consistent with astroparticle physics and
collider experiments, and provide a fit to the energy spectrum of the excess.
The neutralino is a Bino/Higgsino or Bino/Wino/Higgsino mixture with a mass in
the range ~GeV or ~GeV annihilating into W bosons. A third
solutions is found for a neutralino of mass ~GeV annihilating into top
quarks. The best solutions yield a Dark Matter relic density . These pMSSM solutions make clear forecasts for LHC, direct and indirect
DM detection experiments. If the MSSM explanation of the excess seen by
Fermi-LAT is correct, a DM signal might be discovered soon.Comment: Large extension of previous paper: 2 more solutions found in the MSSM
(Bino-Higgsino, Bino-Wino-Higgsino into WW and Bino into ttbar), added
description on extra fit uncertainties, added description on flavor
observables, added discussion on dwarf limit
The perception of psychosocial risks and work-related stress in relation to job insecurity and gender differences: a cross-sectional study
Introduction.The perception of psychosocial risks exposesworkers to developwork-related stress. Recently the attention of scientific
research has focused on a psychosocial risk already identified as “job insecurity” that regards the “overall concern about the
continued existence of the job in the future” and that also depends onworker’s perception, different for each gender. Aimof the Study.
The aim of this cross sectional study is to show if job insecurity, in the formof temporary contracts, can influence the perception of
psychosocial risks and therefore increase worker’s vulnerability to work-related stress and how the magnitude of this effect differs
between genders. Materials and Methods. 338 administrative technical workers (113 males and 225 females) were administered a
questionnaire, enquiring contract typology (permanent or temporary contracts), and the Health Safety Executive questionnaire
to assess work-related stress. The Health Safety Executive Analysis Tool software was used to process collected questionnaires
and theWilcoxon rank-sum test was used to evaluate the statistical significance of the differences obtained. Results. Workers with
temporary contracts obtained lower scores than workers with permanent contracts in all the domains explored by theHealth Safety
Executive Analysis questionnaire, statistically significant (P<0,05). The female workers obtained lower scores than male workers in
all domains explored by the Health Safety Executive questionnaire. Conclusions. Authors conclude that perception of psychosocial
risks can be influenced by job insecurity, in the form of temporary contracts, and increases worker’s vulnerability to work-related
stress and differs between genders
Fault Injection Analytics: A Novel Approach to Discover Failure Modes in Cloud-Computing Systems
Cloud computing systems fail in complex and unexpected ways due to unexpected
combinations of events and interactions between hardware and software
components. Fault injection is an effective means to bring out these failures
in a controlled environment. However, fault injection experiments produce
massive amounts of data, and manually analyzing these data is inefficient and
error-prone, as the analyst can miss severe failure modes that are yet unknown.
This paper introduces a new paradigm (fault injection analytics) that applies
unsupervised machine learning on execution traces of the injected system, to
ease the discovery and interpretation of failure modes. We evaluated the
proposed approach in the context of fault injection experiments on the
OpenStack cloud computing platform, where we show that the approach can
accurately identify failure modes with a low computational cost.Comment: IEEE Transactions on Dependable and Secure Computing; 16 pages. arXiv
admin note: text overlap with arXiv:1908.1164
Calibration of Soil Amplification Factors for Real-Time Ground-Motion Scenarios in Italy
This study deals with the calibration of soil amplification factors to be used for generating site-specific, real-time (or quasi real-time) ground-motion scenarios in Italy. To this end, the ground response of 100 soil profiles is studied through 1-dimensional (1D) equivalent-linear numerical simulations. Several real, rock ground-motion time histories, grouped into different peak ground acceleration (PGA) classes, are driven through the models of the soil columns. Soil amplification factors are then calculated using different definitions, either as the ratio of the spectral acceleration at the surface to the spectral acceleration at the rock outcrop or by dividing the (acceleration or pseudo-velocity) response spectrum intensity at the surface to the reference response spectrum intensity. Finally, regression analyses are performed to derive empirical equations that relate the amplification factor to different soil parameters, such as the average shear wave velocity VS,30 in the top 30 m of a soil profile and the soil fundamental frequency, f0. The reliability of the amplification factors here calculated is verified through comparison with experimental data recorded during the April 6, 2009 L’Aquila earthquake (Mw = 6.3)
Measuring financial integration in new EU member states
The study considers three broad categories of financial integration measures: (i) price-based, which capture discrepancies in asset prices across different national mar kets; (ii) news-based, which analyse the impact that common factors have on the return process of an asset; (iii) quantity-based, which aim at quantifying the effects of frictions on the demand for and supply of securities. This paper finds that financial markets in the new EU Member States (plus Cyprus, Malta and Slovenia) are significantly less integrated than those of the euro area. Nevertheless, there is strong evidence that the process of integration is well under way and has accelerated since accession to the EU
A Latency-driven Availability Assessment for Multi-Tenant Service Chains
Nowadays, most telecommunication services adhere to the Service Function Chain (SFC) paradigm, where network functions are implemented via software. In particular, container virtualization is becoming a popular approach to deploy network functions and to enable resource slicing among several tenants. The resulting infrastructure is a complex system composed by a huge amount of containers implementing different SFC functionalities, along with different tenants sharing the same chain. The complexity of such a scenario lead us to evaluate two critical metrics: the steady-state availability (the probability that a system is functioning in long runs) and the latency (the time between a service request and the pertinent response). Consequently, we propose a latency-driven availability assessment for multi-tenant service chains implemented via Containerized Network Functions (CNFs). We adopt a multi-state system to model single CNFs and the queueing formalism to characterize the service latency. To efficiently compute the availability, we develop a modified version of the Multidimensional Universal Generating Function (MUGF) technique. Finally, we solve an optimization problem to minimize the SFC cost under an availability constraint. As a relevant example of SFC, we consider a containerized version of IP Multimedia Subsystem, whose parameters have been estimated through fault injection techniques and load tests
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