138 research outputs found
Self-reported impact of the COVID-19 pandemic and lockdown on young patients with tic disorders: findings from a case\u2013control study
Background: Little is known about the perceived impact of the COVID-19 pandemic and subsequent lockdown measures on young patients with tic disorders. Previous studies focused on clinician and parent ratings of tic severity, whereas the only international self-report data are available for adult populations. We present the first findings from a case\u2013control study on children and adolescents with tics during lockdown in Italy. Methods: We surveyed 49 patients aged 6\u201318 years and 245 matched controls with a newly developed questionnaire covering socio-demographic and clinical data, as well as lockdown-related changes to daily life activities. Results: About half (53.2%) of the Italian school-age patients who took part in our survey experienced changes in tic severity during lockdown. Perceived increases in tic severity (29.8%) were reported more often than decreases (23.4%). Analogous trends were reported for perceived restlessness and, more significantly, irritability, whereas changes in pain symptoms were less common and were similar in both directions. The presence of tics was associated with increased difficulties with remote learning (p = 0.01), but decreased feelings of missing out on social interactions with schoolmates (p = 0.03). Conclusions: Self-reported data on the impact of COVID-19 lockdown in school-age patients with tic disorders indicate perceived changes in tic severity, as well as restlessness and irritability, in about half of the cases. These findings could guide both clinicians and teachers in the implementation of targeted adjustments in the delivery of care and educational strategies, respectively
Investigating the effects of COVID-19 lockdown on Italian children and adolescents with and without neurodevelopmental disorders: a cross-sectional study
We conducted a cross-sectional study to compare the impact of social distancing and lifestyle changes that occurred during Corona Virus Disease 2019 (COVID-19) lockdown on children and adolescents with and without Neurodevelopmental Disorders (NDDs). An online questionnaire was administered in order to investigate the effects of NDD condition, socio-demographic status, familiar/home environment and COVID-19 exposure on their lives during a two months period of social isolation. We used logistic regression, focusing on five endpoints (remote learning, lifestyle, stress/anxiety, sociality, scolding) to define the extent of these effects. Most questions were paired up to parents and children, to verify the occurrence of agreement. 8305 questionnaires were analyzed, 1362 of which completed by NDDs and 6943 by controls. Results showed that the presence of a NDD, compared to controls, had a significant impact on: Remote Learning (i.e. subjects with NDDs experienced more difficulties in attending online classes and studying), Sociality (i.e. subjects with NDDs missed their schoolmates less), Scolding (i.e. subjects with NDDs were scolded more often) and Anxiety (i.e. subjects with NDDs were perceived by their parents as more anxious). Substantial agreement between parents and children arose from questions concerning Remote learning, Lifestyle and Scolding. The current study actually points out that having a NDD gives account for a stronger influence on school performance and on behavioral and psychological aspects, during a two months lockdown. Such results may provide useful information to governments and school authorities on how carrying through supportive strategies for youth affected by NDDs
Supernova 1987A did not test the neutrino mass hierarchy
We dispel the misconception that data from SN 1987A favor the normal neutrino
mass hierarchy over the inverted hierarchy for \sin^2 \theta_{13} \gsim
10^{-4}. We find comparable fits for the two hierarchies. No bound can be
placed on the mixing angle even at the 1 level.Comment: 15 pages, 9 figure
Probing the neutrino mass hierarchy and the 13-mixing with supernovae
We consider in details the effects of the 13-mixing (sin^2 theta_{13}) and of
the type of mass hierarchy/ordering (sign[ Delta m^2_{13}]) on neutrino signals
from the gravitational collapses of stars. The observables (characteristics of
the energy spectra of nu_e and antinu_e events) sensitive to sin^2 theta_{13}
and sign[Delta m^2_{13}] have been calculated. They include the ratio of
average energies of the spectra, r_E = /, the ratio of widths of
the energy distributions, r_Gamma, the ratios of total numbers of nu_e and
antinu_e events at low energies, S, and in the high energy tails, R_{tail}. We
construct and analyze scatter plots which show the predictions for the
observables for different intervals of sin^2 theta_{13} and signs of Delta
m^2_{13}, taking into account uncertainties in the original neutrino spectra,
the star density profile, etc.. Regions in the space of observables r_E,
r_Gamma, S, R_{tail} exist in which certain mass hierarchy and intervals of
sin^2 theta_{13} can be identified or discriminated. We elaborate on the method
of the high energy tails in the spectra of events. The conditions are
formulated for which sin^2 theta_{13} can be (i) measured, (ii) restricted from
below, (iii) restricted from above. We comment on the possibility to determine
sin^2 theta_{13} using the time dependence of the signals due to the
propagation of the shock wave through the resonance layers of the star. We show
that the appearance of the delayed Earth matter effect in one of the channels
(nu_e or antinu_e) in combination with the undelayed effect in the other
channel will allow to identify the shock wave appeareance and determine the
mass hierarchy.Comment: LaTeX, 56 pages, 12 figures; a few clarifications added; typos
corrected. Version to appear in JCA
High motor variability in DYT1 dystonia is associated with impaired visuomotor adaptation.
For the healthy motor control system, an essential regulatory role is maintaining the equilibrium between keeping unwanted motor variability in check whilst allowing informative elements of motor variability. Kinematic studies in children with generalised dystonia (due to mixed aetiologies) show that movements are characterised by increased motor variability. In this study, the mechanisms by which high motor variability may influence movement generation in dystonia were investigated. Reaching movements in the symptomatic arm of 10 patients with DYT1 dystonia and 12 age-matched controls were captured using a robotic manipulandum and features of motor variability were extracted. Given that task-relevant variability and sensorimotor adaptation are related in health, markers of variability were then examined for any co-variance with performance indicators during an error-based learning visuomotor adaptation task. First, we confirmed that motor variability on a trial-by-trial basis was selectively increased in the homogenous and prototypical dystonic disorder DYT1 dystonia. Second, high baseline variability predicted poor performance in the subsequent visuomotor adaptation task offering insight into the rules which appear to govern dystonic motor control. The potential mechanisms behind increased motor variability and its corresponding implications for the rehabilitation of patients with DYT1 dystonia are highlighted
Cosmological and Astrophysical Neutrino Mass Measurements
Cosmological and astrophysical measurements provide powerful constraints on
neutrino masses complementary to those from accelerators and reactors. Here we
provide a guide to these different probes, for each explaining its physical
basis, underlying assumptions, current and future reach.Comment: 11 page
Hiding relativistic degrees of freedom in the early universe
We quantify the extent to which extra relativistic energy density can be
concealed by a neutrino asymmetry without conflicting with the baryon asymmetry
measured by the Wilkinson Microwave Anisotropy Probe (WMAP). In the presence of
a large electron neutrino asymmetry, slightly more than seven effective
neutrinos are allowed by Big Bang Nucleosynthesis (BBN) and WMAP at 2\sigma.
The same electron neutrino degeneracy that reconciles the BBN prediction for
the primordial helium abundance with the observationally inferred value also
reconciles the LSND neutrino with BBN by suppressing its thermalization prior
to BBN.Comment: 5 pages, 5 figure
Supernova neutrino oscillations: A simple analytical approach
Analyses of observable supernova neutrino oscillation effects require the
calculation of the electron (anti)neutrino survival probability P_ee along a
given supernova matter density profile. We propose a simple analytical
prescription for P_ee, based on a double-exponential form for the crossing
probability and on the concept of maximum violation of adiabaticity. In the
case of two-flavor transitions, the prescription is shown to reproduce
accurately, in the whole neutrino oscillation parameter space, the results of
exact numerical calculations for generic (realistic or power-law) profiles. The
analytical approach is then generalized to cover three-flavor transitions with
(direct or inverse) mass spectrum hierarchy, and to incorporate Earth matter
effects. Compact analytical expressions, explicitly showing the symmetry
properties of P_ee, are provided for practical calculations.Comment: 22 pages (RevTeX) + 5 figures (PostScript
Superluminal neutrinos in long baseline experiments and SN1987a
Precise tests of Lorentz invariance in neutrinos can be performed using long
baseline experiments such as MINOS and OPERA or neutrinos from astrophysical
sources. The MINOS collaboration reported a measurement of the muonic neutrino
velocities that hints to super-luminal propagation, very recently confirmed at
6 sigma by OPERA. We consider a general parametrisation which goes beyond the
usual linear or quadratic violation considered in quantum-gravitational models.
We also propose a toy model showing why Lorentz violation can be specific to
the neutrino sector and give rise to a generic energy behaviour E^alpha, where
alpha is not necessarily an integer number. Supernova bounds and the preferred
MINOS and OPERA regions show a tension, due to the absence of shape distortion
in the neutrino bunch in the far detector of MINOS. The energy independence of
the effect has also been pointed out by the OPERA results.Comment: 22 pages, 7 figures; comment on Cherenkov emission added, version
matching JHEP published pape
The MSW effect and Matter Effects in Neutrino Oscillations
The MSW (Mikheyev-Smirnov-Wolfenstein) effect is the adiabatic or partially
adiabatic neutrino flavor conversion in medium with varying density. The main
notions related to the effect, its dynamics and physical picture are reviewed.
The large mixing MSW effect is realized inside the Sun providing the solution
of the solar neutrino problem. The small mixing MSW effect driven by the 1-3
mixing can be realized for the supernova (SN) neutrinos. Inside the collapsing
stars new elements of the MSW dynamics may show up: the non-oscillatory
transition, non-adiabatic conversion, time dependent adiabaticity violation
induced by shock waves. Effects of the resonance enhancement and the parametric
enhancement of oscillations can be realized for the atmospheric and accelerator
neutrinos in the Earth. Precise results for neutrino oscillations in the low
density medium with arbitrary density profile are presented and the attenuation
effect is described. The area of applications is the solar and SN neutrinos
inside the Earth, and the results are crucial for the neutrino oscillation
tomography.Comment: 18 pages, latex, 6 figures, talk given at the Nobel Symposium 129,
``Neutrino Physics'', Haga Slott, August 19 - 24, 200
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