496 research outputs found
Dissipative continuous Euler flows
We show the existence of continuous periodic solutions of the 3D
incompressible Euler equations which dissipate the total kinetic energy
A network model of Italy shows that intermittent regional strategies can alleviate the COVID-19 epidemic
The COVID-19 epidemic hit Italy particularly hard, yielding the implementation of strict national lockdown rules. Previous modelling studies at the national level overlooked the fact that Italy is divided into administrative regions which can independently oversee their own share of the Italian National Health Service. Here, we show that heterogeneity between regions is essential to understand the spread of the epidemic and to design effective strategies to control the disease. We model Italy as a network of regions and parameterize the model of each region on real data spanning over two months from the initial outbreak. We confirm the effectiveness at the regional level of the national lockdown strategy and propose coordinated regional interventions to prevent future national lockdowns, while avoiding saturation of the regional health systems and mitigating impact on costs. Our study and methodology can be easily extended to other levels of granularity to support policy- and decision-makers
Analysis of extended genomic rearrangements in oncological research.
Screening for genomic rearrangements is a fundamental task in the genetic diagnosis of many inherited
disorders including cancer-predisposing syndromes. Several methods were developed for analysis of structural
genomic abnormalities, some are targeted to the analysis of one or few specific loci, others are designed to
scan the whole genome. Locus-specific methods are used when the candidate loci responsible for the specific
pathological condition are known. Whole-genome methods are used to discover loci bearing structural
abnormalities when the disease-associated locus is unknown. Three main approaches have been employed for
the analysis of locus-specific structural changes. The first two are based on probe hybridization and include
cytogenetics and DNA blotting. The third approach is based on PCR amplification and includes microsatellite or
single nucleotide polymorphism (SNP) genotyping, relative allele quantitation, real-time quantitative PCR, long
PCR and multiplex PCR-based methods such as multiplex ligation-dependent probe amplification and the
recently developed nonfluorescent multiplex PCR coupled to high-performance liquid chromatography analysis.
Whole-genome methods include cytogenetic methods, array-comparative genomic hybridization, SNP array
and other sequence-based methods. The goal of the present review is to provide an overview of the main
features and advantages and limitations of methods for the screening of structural genomic abnormalities
relevant to oncological research
High-resolution tracking in a GEM-Emulsion detector
SHiP (Search for Hidden Particles) is a beam dump experiment proposed at the
CERN SPS aiming at the observation of long lived particles very weakly coupled
with ordinary matter mostly produced in the decay of charmed hadrons. The beam
dump facility of SHiP is also a copious factory of neutrinos of all three kinds
and therefore a dedicated neutrino detector is foreseen in the SHiP apparatus.
The neutrino detector exploits the Emulsion Cloud Chamber technique with a
modular structure, alternating walls of target units and planes of electronic
detectors providing the time stamp to the event. GEM detectors are one of the
possible choices for this task. This paper reports the results of the first
exposure to a muon beam at CERN of a new hybrid chamber, obtained by coupling a
GEM chamber and an emulsion detector. Thanks to the micrometric accuracy of the
emulsion detector, the position resolution of the GEM chamber as a function of
the particle inclination was evaluated in two configurations, with and without
the magnetic fiel
Unequal effects of the national lockdown on mental and social health in Italy
With the exception of a few countries that chose a different approach, the worldwide reaction to the COVID-19 pandemic was a (longer or shorter) period of national lockdown. While the economic consequences of shutting down national economies were immediately evident, the sociopsychiatric implications of the social confinement of the entire population remain hidden and not fully understood. Italy has been the first European country to be severely impacted by the COVID-19 pandemic, to which it responded through strict lockdown measurements. The results of a timely survey on mental and social health, carried out by students and teachers of a middle school in Rome, might help identify the most vulnerable groups of the population. This evidence could be crucial in conceiving and enacting targeted public health policies to mitigate the consequences of the pandemic on mental health and to prevent intolerance to containment measures in some population segments, which could hamper worldwide efforts in the fight against COVID-19
Low energy high angular resolution neutral atom detection by means of micro-shuttering techniques: the BepiColombo SERENA/ELENA sensor
The neutral sensor ELENA (Emitted Low-Energy Neutral Atoms) for the ESA
cornerstone BepiColombo mission to Mercury (in the SERENA instrument package)
is a new kind of low energetic neutral atoms instrument, mostly devoted to
sputtering emission from planetary surfaces, from E ~20 eV up to E~5 keV,
within 1-D (2x76 deg). ELENA is a Time-of-Flight (TOF) system, based on
oscillating shutter (operated at frequencies up to a 100 kHz) and mechanical
gratings: the incoming neutral particles directly impinge upon the entrance
with a definite timing (START) and arrive to a STOP detector after a flight
path. After a brief dissertation on the achievable scientific objectives, this
paper describes the instrument, with the new design techniques approached for
the neutral particles identification and the nano-techniques used for designing
and manufacturing the nano-structure shuttering core of the ELENA sensor. The
expected count-rates, based on the Hermean environment features, are shortly
presented and discussed. Such design technologies could be fruitfully exported
to different applications for planetary exploration.Comment: 11 page
Environmental sub-MeV neutron measurement at the Gran Sasso surface laboratory with a super-fine-grained nuclear emulsion detector
The measurement of environmental neutrons is particularly important in the
search for new physics, such as dark matter particles, because neutrons
constitute an often-irreducible background source. The measurement of the
neutron energy spectra in the sub-MeV scale is technically difficult because it
requires a very good energy resolution and a very high -ray rejection
power. In this study, we used a super-fine-grained nuclear emulsion, called
Nano Imaging Tracker (NIT), as a neutron detector. The main target of neutrons
is the hydrogen (proton) content of emulsion films. Through a topological
analysis, proton recoils induced by neutron scattering can be detected as
tracks with sub-micrometric accuracy. This method shows an extremely high
-ray rejection power, at the level of , which is equivalent to 5 years accumulation of environmental
-rays, and a very good energy and direction resolution even in the
sub-MeV energy region. In order to carry out this measurement with sufficient
statistics, we upgraded the automated scanning system to achieve a speed of 250
g/year/machine. We calibrated the detector performance of this system with 880
keV monochromatic neutrons: a very good agreement with the expectation was
found for all the relevant kinematic variables. The application of the
developed method to a sample exposed at the INFN Gran Sasso surface laboratory
provided the first measurement of sub-MeV environmental neutrons with a flux of
in the proton energy
range between 0.25 and 1 MeV (corresponds to neutron energy range between 0.25
and 10 MeV), consistent with the prediction. The neutron energy and direction
distributions also show a good agreement.Comment: 11 pages, 14 figure
The geometry of a vorticity model equation
We provide rigorous evidence of the fact that the modified
Constantin-Lax-Majda equation modeling vortex and quasi-geostrophic dynamics
describes the geodesic flow on the subgroup of orientation-preserving
diffeomorphisms fixing one point, with respect to right-invariant metric
induced by the homogeneous Sobolev norm and show the local existence
of the geodesics in the extended group of diffeomorphisms of Sobolev class
with .Comment: 24 page
Prognostic value of gender and primary tumor location in metastatic colon cancer
Sex might influence prognosis in patients affected by colorectal cancer. We retrospectively studied a cohort of patients affected by metastatic colon cancer (mCC) stratified by sex and primary tumor location. RAS mutational status was also included in the analysis. Overall, 616 patients met the eligibility criteria, 261 women and 355 men. Neither gender, nor RAS mutational status influenced overall survival (OS) in the entire population. As expected, patients with right-sided colon cancer (RCC) had a significant shorter OS compared to those with left-sided colon cancer (LCC) (21.3 vs 33.1 months, p= 0.002). When the analysis was performed stratifying for gender, RCC retained worse prognosis among men (OS 20.5 vs 33.9 months, p= 0.008), but not among women (p= 0.132). Similarly, the presence of RAS mutations had no prognostic effect in women, but was significantly associate with shorter survival in men (OS 29.5 vs 33.7 months, p= 0.046). In addition, when comparing clinical outcome of women or men according to sidedness and RAS mutational status, RCC was associated with dismal prognosis only in men with RAS mutated tumor (OS 17.2 vs 32.3 months, p= 0.008). Our study highlights the importance of gender in the outcome of patients with mCC
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