109 research outputs found
The Comparative Exploration of the Ice Giant Planets with Twin Spacecraft: Unveiling the History of our Solar System
In the course of the selection of the scientific themes for the second and
third L-class missions of the Cosmic Vision 2015-2025 program of the European
Space Agency, the exploration of the ice giant planets Uranus and Neptune was
defined "a timely milestone, fully appropriate for an L class mission". Among
the proposed scientific themes, we presented the scientific case of exploring
both planets and their satellites in the framework of a single L-class mission
and proposed a mission scenario that could allow to achieve this result. In
this work we present an updated and more complete discussion of the scientific
rationale and of the mission concept for a comparative exploration of the ice
giant planets Uranus and Neptune and of their satellite systems with twin
spacecraft. The first goal of comparatively studying these two similar yet
extremely different systems is to shed new light on the ancient past of the
Solar System and on the processes that shaped its formation and evolution.
This, in turn, would reveal whether the Solar System and the very diverse
extrasolar systems discovered so far all share a common origin or if different
environments and mechanisms were responsible for their formation. A space
mission to the ice giants would also open up the possibility to use Uranus and
Neptune as templates in the study of one of the most abundant type of
extrasolar planets in the galaxy. Finally, such a mission would allow a
detailed study of the interplanetary and gravitational environments at a range
of distances from the Sun poorly covered by direct exploration, improving the
constraints on the fundamental theories of gravitation and on the behaviour of
the solar wind and the interplanetary magnetic field.Comment: 29 pages, 4 figures; accepted for publication on the special issue
"The outer Solar System X" of the journal Planetary and Space Science. This
article presents an updated and expanded discussion of the white paper "The
ODINUS Mission Concept" (arXiv:1402.2472) submitted in response to the ESA
call for ideas for the scientific themes of the future L2 and L3 space
mission
Reconstruction scheme for excitatory and inhibitory dynamics with quenched disorder: application to zebrafish imaging
Reconstruction scheme for excitatory and inhibitory dynamics with quenched disorder: application to zebrafish imaging
An inverse procedure is developed and tested to recover functional and
structural information from global signals of brains activity. The method
assumes a leaky-integrate and fire model with excitatory and inhibitory
neurons, coupled via a directed network. Neurons are endowed with a
heterogenous current value, which sets their associated dynamical regime. By
making use of a heterogenous mean-field approximation, the method seeks to
reconstructing from global activity patterns the distribution of in-coming
degrees, for both excitatory and inhibitory neurons, as well as the
distribution of the assigned currents. The proposed inverse scheme is first
validated against synthetic data. Then, time-lapse acquisitions of a zebrafish
larva recorded with a two-photon light sheet microscope are used as an input to
the reconstruction algorithm. A power law distribution of the in-coming
connectivity of the excitatory neurons is found. Local degree distributions are
also computed by segmenting the whole brain in sub-regions traced from
annotated atlas
Effectiveness of a stepped-care programme of WHO psychological interventions in migrant populations resettled in Italy: study protocol for the RESPOND randomized controlled trial
Introduction: Migrant populations, including workers, undocumented migrants, asylum seekers, refugees, internationally displaced persons, and other populations on the move, are exposed to a variety of stressors and potentially traumatic events before, during, and after the migration process. In recent years, the COVID-19 pandemic has represented an additional stressor, especially for migrants on the move. As a consequence, migration may increase vulnerability of individuals toward a worsening of subjective wellbeing, quality of life, and mental health, which, in turn, may increase the risk of developing mental health conditions. Against this background, we designed a stepped-care programme consisting of two scalable psychological interventions developed by the World Health Organization and locally adapted for migrant populations. The effectiveness and cost-effectiveness of this stepped-care programme will be assessed in terms of mental health outcomes, resilience, wellbeing, and costs to healthcare systems. Methods and analysis: We present the study protocol for a pragmatic randomized study with a parallel-group design that will enroll participants with a migrant background and elevated level of psychological distress. Participants will be randomized to care as usual only or to care a usual plus a guided self-help stress management guide (Doing What Matters in Times of Stress, DWM) and a five-session cognitive behavioral intervention (Problem Management Plus, PM+). Participants will self-report all measures at baseline before random allocation, 2 weeks after DWM delivery, 1 week after PM+ delivery and 2 months after PM+ delivery. All participants will receive a single-session of a support intervention, namely Psychological First Aid. We will include 212 participants. An intention-to-treat analysis using linear mixed models will be conducted to explore the programme's effect on anxiety and depression symptoms, as measured by the Patient Health Questionnaire—Anxiety and Depression Scale summary score 2 months after PM+ delivery. Secondary outcomes include post-traumatic stress disorder symptoms, resilience, quality of life, resource utilization, cost, and cost-effectiveness. Discussion: This study is the first randomized controlled trial that combines two World Health Organization psychological interventions tailored for migrant populations with an elevated level of psychological distress. The present study will make available DWM/PM+ packages adapted for remote delivery following a task-shifting approach, and will generate evidence to inform policy responses based on a more efficient use of resources for improving resilience, wellbeing and mental health
Stability of the Jupiter Southern Polar Vortices Inspected Through Vorticity Using Juno/JIRAM Data
The Jovian InfraRed Auroral Mapper (JIRAM) onboard the NASA Juno mission monitored the evolution of Jupiter’s polar cyclones since their first observation ever in February 2017. Data acquired by JIRAM have revealed cloudy cyclones organized in a complex, yet stable geometrical pattern at both poles. Several studies have investigated the dynamics and the structure of these cyclones, to understand the physical mechanisms behind their formation and evolution. In this work, we present vorticity maps deduced from the wind fields for the region poleward of ∼−80°, which has been extensively covered over the last four years of observations. The cyclonic features related to the stable polar cyclones are embedded in a slightly, but diffused anticyclonic circulation, in which short-living anticyclones emerge with respect to the surroundings. Although the general stability of both the cyclones and the whole system is strongly confirmed by this work, variations in the shape of the vortices, as well as changes in the local structures, have been observed
Five Years of Observations of the Circumpolar Cyclones of Jupiter
The regular polygons of circumpolar cyclones, discovered by Juno in 2017, are one of the most puzzling features of Jupiter. Here we show new recent global pictures of the North polar cyclones' structure. These are the first simultaneous images of the whole structure since 2017, and we find that it remained almost unperturbed, just like the South one. The observation of these long-lasting structures poses questions regarding the formation mechanism of cyclones, and on their vertical structure. Data by Juno/JIRAM infrared camera collected over the last 5 years show that cyclones migrate around what may seem like equilibrium positions, with timescales of a few months but, aside from that, the cyclones systems are very stable. Our analysis of the observations shows that the motion of cyclones around their equilibrium position is uncorrelated with their position if a barotropic approximation (β-drift) is assumed. Thus, a different dynamical explanation than the barotropic β-drift is needed to explain the stability of the observed features. Each cyclone has a peculiar morphology, which differs from the others and is stable over the observed lapse of time in most cases
Clinical characteristics and risk factors associated with COVID-19 severity in patients with haematological malignancies in Italy: a retrospective, multicentre, cohort study
Several small studies on patients with COVID-19 and haematological malignancies are available showing a high mortality in this population. The Italian Hematology Alliance on COVID-19 aimed to collect data from adult patients with haematological malignancies who required hospitalisation for COVID-19
Mapping Io's Surface Composition With Juno/JIRAM
The surface composition of Io is dominated by SO2 frost, plus other chemical species identified or proposed over the past decades by combining Earth-based and space-based observations with laboratory data. Here we discuss spectroscopic data sets of Io obtained by the Jovian InfraRed Auroral Mapper (JIRAM) spectro-imager onboard Juno in nine orbits, spanning a 3-year period. We display average spectral profiles of Io in the 2-5 μm range, and we use band depths derived from those profiles to map the geographic distribution of SO2 frost and other spectral features. This data set allows for an ~22% surface coverage at 58 to 162 km/px and in a broad range of latitudes. Our results confirm the broadly regional SO2-frost trends already highlighted by Galileo/NIMS. Io's average spectral profiles as well as the mapping of the 4.47-μm band also confirm that SO2 exists in the 32S16O18O isotopic form. Surprisingly, the mapping performed by JIRAM shows that the absorption band at 2.1 μm is unrelated to SO2 frost, while we map for the first time the depth of the 2.65-μm band, highlighting regions enriched in this absorber, possibly H2S. JIRAM data confirm that the 3.92-μm band, likely due to Cl2SO2, is largely related to the SO2 distribution. The correlation between Cl2SO2 and ClSO2, possibly revealed at 4.62 μm, is not equally clear. The simultaneous presence of two very weak spectral features at 4.55 and 4.62 μm suggests that nitrile compounds or tholins may also be present on the surface
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