742 research outputs found
Magnetic fields in galaxy clusters in the Square Kilometre Array era
A new era for radio astronomy is coming. The Square Kilometre Array, with its unprecedented capabilities will revolutionize our knowledge of the Universe, opening new challenges to many fields of research: from astronomy to technology, passing by the big data problem. As astrophysicists, to be ready for this revolution, we have to understand how to manage in the best way the data that the SKA will collect. The purpose of this work is to address what is the origin of magnetic fields in the Universe and it is mainly focussed on the characterization of magnetic fields in galaxy clusters. These are ideal systems to study the properties of large scale magnetic fields as well as the relativistic particles that populate the intracluster medium. Indeed, direct manifestations of the aforementioned non-thermal components in clusters are given by the diffuse synchrotron sources named radio haloes, relics, and mini-haloes. All of these sources present low-surface brightness that makes them very elusive for the current radio telescopes. With the high sensitivity level expected for the SKA, the number of detected diffuse synchrotron sources will grow giving us the chance to characterize intracluster magnetic fields in a bigger sample of clusters. Going to kpc scales, polarized discrete radio sources play a decisive role in determining the strength and the structure of large scale magnetic fields. The Faraday rotation of the polarization plane of these sources, caused by the passage through a magneto-ionic medium, depends on the medium itself and can be used to constrain the properties of the magnetic field responsible for the rotation. So far, this approach has been applied in a limited number of galaxy clusters but the expectations for the SKA are extremely promising. To investigate how the study of the diffuse and discrete sources can help to shed light on cosmic magnetism, I pursued a two approaches: on one side, I conducted and analysed radio observations of galaxy clusters to infer the properties of their non-thermal component, on the other side, I realized a framework to produce the polarized sky that the SKA will detect. The combination of these two approaches let us understand what are the best strategies to constrain large scale magnetic fields and it is the starting point to get prepared for the SKA
WOMAN PIONEER SOCIOLOGICAL ANALYSIS OF MICRO FACTORS REGARDING THE ROLE OF MIGRATORY WOMEN FROM EASTERN EUROPE
The 90s were the stage of a new type of migration from Eastern Europe that saw women for the first time in the sociological role of pioneer.The countries of origin most interested in the phenomena were mostly the Russophone ones, above all Ukraine. On the other hand, the favored receiving country within the European Union has been - since the beginning - Italy. In fact, following the Eurostat data of 2020, of the approximately 800,000 Ukrainians residing in the EU, we see that over a quarter are in Italy with an overwhelming majority on the female front. The 177,000 residents are about 37% of all Ukrainian women in Europe.One of the macro-sociological reasons envisioned by the expert was the fall of the Eastern bloc, but what were the causes at the micro sociological level that led these social actors to choose one destination rather than another? What are the causes that have favored this type of immigration in the area?The paper aims to analyze the social changes that invested the European countries and above all Italy, which have been prepared the ground for these new migratory movements since the 1980s. The case study is based on the Russophone community of Cagliari, main city of Sardinia region, an Italian island in the center of the Mediterranean Sea, where the Russophone immigrant community had the opportunity to integrate and start an active cultural exchange thanks to the work of some Cultural Associations which were already active in the area
Nuto Revelli: voci e memorie dal "mondo dei vinti" tra storia e microstoria
Volunteer on the Russian front and then partisan during the Second World War, Nuto Revelli devoted his whole life to recovering the life stories of history “defeated”: the survivor and MIA soldiers, the men and women from the countryside of Cuneo.But, in actual fact, who was Nuto Revelli? This paper tries to offer an answer to the question, through a brief excursus on the author’s biography and works, which were marked by an undeniable interdisciplinarity.Volontario sul fronte russo e poi partigiano durante la Seconda guerra mondiale, Nuto Revelli ha dedicato la propria vita al recupero delle testimonianze di vita dei “vinti” della storia: i reduci e i dispersi, i contadini e le contadine del Cuneese.Ma chi è stato davvero Nuto Revelli? Il seguente contributo cerca di offrire una risposta alla domanda, attraverso un breve excursus sul percorso biografico e intellettuale dell’autore, contraddistinto da una marcata interdisciplinarità
Le strategie dei governi locali di fronte alle politiche di spending review
A partire dagli anni settanta, del secondo appena trascorso, il passaggio da un'economia di stampo keynesiano-fordista ad una neoliberista, ha sancito il passaggio ad uno Stato "glocalizzato" (Brenner, 2004). La selettività dello Stato (Jessop, 2005) è divenuta spaziale, dando luogo ad una governance multilivello, che provocando una "riscalizzazione" delle forme di gestione dello Stato ha determinato da parte di molti paesi l'adozione di processi di decentramento della finanza pubblica. Contestualmente la crisi economica, ha richiesto un importante impegno in tema di riordino dei conti pubblici. Il lavoro si propone di offrire spunti di riflessioni circa l'esito di questi processi sulle municipalità italiane, analizzando l'impatto provocato sui territori, in termini di disparità regionale
Is it possible to compare inhibitory and excitatory intracortical circuits in face and hand primary motor cortex?
Face muscles are important in a variety of different functions, such as feeding, speech and communication of non-verbal affective states, which require quite different patterns of activity from those of a typical hand muscle. We ask whether there are differences in their neurophysiological control that might reflect this. Fifteen healthy individuals were studied. Standard single- and paired-pulse transcranial magnetic stimulation (TMS) methods were used to compare intracortical inhibitory (short interval intracortical inhibition (SICI); cortical silent period (CSP)) and excitatory circuitries (short interval intracortical facilitation (SICF)) in two typical muscles, the depressor anguli oris (DAO), a face muscle, and the first dorsal interosseous (FDI), a hand muscle. TMS threshold was higher in DAO than in FDI. Over a range of intensities, resting SICF was not different between DAO and FDI, while during muscle activation SICF was stronger in FDI than in DAO (P = 0.012). At rest, SICI was stronger in FDI than in DAO (P = 0.038) but during muscle contraction, SICI was weaker in FDI than in DAO (P = 0.034). We argue that although many of the difference in response to the TMS protocols could result from the difference in thresholds, some, such as the reduction of resting SICI in DAO, may reflect fundamental differences in the physiology of the two muscle groups
Less air pollution did not explain the decline in admissions for AMI during the first wave of COVID-19 pandemic in Sardinia, Italy
During the COVID-19 pandemic, hospitalizations for acute myocardial infarction (AMI) decreased worldwide. We compared the admissions for AMI in the four regional 24/7 cath lab during the national lockdown, the 8 weeks before the lockdown, the 8 weeks after the e lockdown, and the corresponding time period in 2019 and we analyzed the average level of pollution in the studies areas. A marked decline in AMI admissions was observed during the lockdown period in comparison with the 8 weeks before the lockdown (p < 0.0001) and a significant increase in the 8 weeks after the lockdown (p < 0.00001). No significant change in air pollutants density were highlighted. Since air pollution did not change substantially in our region, the environment factor cannot explain the decline in the number of admissions for AMI we recorded during the lockdown. Fear of contagion is the most plausible reason for the drop of hospitalizations during the lockdown period
Predictors of Bluetongue development in Sardinia (Italy) identification, using multilevel logistic mixed model
Objectives: The Bluetongue Virus is one of the most studied ruminant diseases, affecting particularly sheep and goats. This study aims to identify, for the first time, the specific risk factors influencing the disease development in Sardinia, using multilevel logistic regression model, in order to give a contribution to the sanitary programs and favour the early detection.
Methods: The data of the present retrospective study, collected from informatics systems of Istituto Zooprofilattico della Sardegna, are referred to all 15,780 Sardinian sheep farms observed for 3 years (2012-2014). The outcome of interest was dichotomous and defined the development of Bluetongue outbreak, after serological test or clinical signs. The effect of several region-specific prognostic factors on disease spread was investigated.
Results: The final model indicated that Bluetongue development was significantly associated with an increase in number of animals (P < 0.0001), number of cattle around farm (P < 0.0001), water surface area (P =0.002), and amount of rainfall in the previous days (P < 0.0001). Furthermore, the altitude over 450 MASL (P < 0.0001), the vaccination prophylaxis (P < 0.0001) and the previous outbreak event (P < 0.0001) had a protective effect against the outcome.
Conclusion: The results of this study indicated that number of animals and the amount of rainfall were the most important risk factors that affected the Bluetongue development, while the vaccination prophylaxis was found to be an effective measure in decelerating the disease spread. 
Fiscal federalism and equalization design under the growing public finance constraint: a case of Italian municipalities
Recently, the issue of federalism has turned at the centre of the political debate in Italy. It is basically due to the growing demand of rich northern regions who in 2018 laid down the requests to exercise additional functions retaining a more significant part of revenues that the central government collects in their territories. Another reason for attention to this issue is that the long period of public finance consolidation in Italy (2011-15) put the implementation of fiscal federalism to a standstill. There is a growing demand to ascertain the measure to which this implementation has been biased o remained undone. This paper focuses on this second issue investigating to which extent the design of fiscal federalism reform has been applied to the Italian municipalities with a special focus on the equalization system. The paper first proposes a review on the evolution of public finance setting in Italy before the crisis (2008-09), considering the decentralization process in the 1990s and the Constitutional reform of 2001 followed by the enabling law 42 in 2009. Then it looks at the period of fiscal consolidation after the financial crisis in 2011 focusing on the burden of adjustment measures imposed to Italian municipalities. Finally, it tries to summarize the contradictions that the overlapping of two contrasting political agendas – the centralization of public finance under fiscal consolidation and the ongoing fiscal federalism reform – created for the equalization system of municipalities
Real-Time Monitoring of Cellular Cultures with Electrolyte-Gated Carbon Nanotube Transistors
Cell-based biosensors constitute a fundamental tool in biotechnology, and
their relevance has greatly increased in recent years as a result of a surging
demand for reduced animal testing and for high-throughput and cost-effective in
vitro screening platforms dedicated to environmental and biomedical
diagnostics, drug development and toxicology. In this context,
electrochemical/electronic cell-based biosensors represent a promising class of
devices that enable long-term and real-time monitoring of cell physiology in a
non-invasive and label-free fashion, with a remarkable potential for process
automation and parallelization. Common limitations of this class of devices at
large include the need for substrate surface modification strategies to ensure
cell adhesion and immobilization, limited compatibility with complementary
optical cell-probing techniques, and need for frequency-dependent measurements,
which rely on elaborated equivalent electrical circuit models for data analysis
and interpretation. We hereby demonstrate the monitoring of cell adhesion and
detachment through the time-dependent variations in the quasi-static
characteristic current curves of a highly stable electrolyte-gated transistor,
based on an optically transparent network of printable polymer-wrapped
semiconducting carbon-nanotubes
Charge Transport in High-Mobility Field-Effect Transistors Based on Inkjet Printed Random Networks of Polymer Wrapped Single-Walled Carbon Nanotubes
Printed random networks of polymer-wrapped multi-chiral semiconducting carbon nanotubes (s-SWCNTs) are an opportunity for mass-manufacturable, high-performance large-area electronics. To meet this goal, a deeper understanding of charge-transport mechanisms in such mixed networks is crucial. Here, charge transport in field-effect transistors based on inkjet-printed s-SWCNTs networks is investigated, obtaining direct evidence for the phases probed by charge in the accumulated channel, which is critical information to rationalize the different transport properties obtained for different printing conditions. In particular, when the fraction of nanotubes with smaller bandgaps is efficiently interconnected, the sparse network provides efficient charge percolation for band-like transport, with a charge mobility as high as 20.2 cm(2) V-1 s(-1). However, when the charges are forced by a less efficient morphology, to populate also higher bandgap nanotubes and and/or the wrapping polymer, thermally activated transport takes place and mobility drops. As a result, a trade-off between network density and charge transport properties is identified for device current optimization, in both p- and n-type regimes. These findings shed light on the fundamental aspects related to charge transport in printed s-SWCNT mixed networks and contribute to devise appropriate strategies for the formulation of inks and processes towards cost-effective mass production schemes of high-performance large-area electronics
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