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No full textRiassunti del Workshop “Incontri nella Preistoria” (Progetto LO.RE.DE.MO - FESR
Analisi spaziali intra-site e Geographical Information System per un approccio cognitivo ai modelli di frequentazione antropica del giacimento di Isernia La Pineta (Molise)
No full textTerms and technologies that would be not comprehensible to the archeologists of the past are now
widely spreading inside excavation fields, beginning from those sites where the enormous proportion of
picked data and the continuous overlap of the layers makes difficult to understand what happened.
In this context, the use of the GIS (Geographical Information System) has known a remarkable success,
according to the increasing necessity to archive, elaborate and analyze the great quantity of archaeological
data coming from stratigraphic excavations, as in the case of Isernia La Pinet
Stiff knots
No full textWe report on the geometry and mechanics of knotted stiff strings. We discuss both closed and open knots. Our two main results are that (i) their equilibrium energy as well as the equilibrium tension for open knots depends on the type of knot as the square of the bridge number and (ii) braid localization is found to be a general feature of stiff string entanglements, while angle and knot localizations are forbidden. Moreover, we identify a family of knots for which the equilibrium shape is a circular braid. Two other equilibrium shapes are found from Monte Carlo simulations. These three shapes are confirmed by rudimentary experiments. Our approach is also extended to the problem of the minimization of the length of a knotted string with a maximum allowed curvature
The link between reported cases of COVID-19 and the Infodemic Risk Index: A worldwide perspective
Full text linkIn this brief report we followed the evolution of the COVID-19 Infodemic Risk Index during 2020 and clarified its connection with the epidemic waves, focusing specifically on their co-evolution in Europe, South America, and South-eastern Asia. Using 640 million tweets collected by the Infodemic Observatory and the open access dataset published by Our World in Data regarding COVID-19 worldwide reported cases, we analyze the COVID-19 infodemic vs. pandemic co-evolution from January 2020 to December 2020. We find that a characteristic pattern emerges at the global scale: a decrease in misinformation on Twitter as the number of COVID-19 confirmed cases increases. Similar local variations highlight how this pattern could be influenced both by the strong content moderation policy enforced by Twitter after the first pandemic wave and by the phenomenon of selective exposure that drives users to pick the most visible and reliable news sources available
Complex Urban Systems: Challenges and Integrated Solutions for the Sustainability and Resilience of Cities
Full text linkFor decades, from design theory to urban planning and management, from social sciences to urban environmental science, cities have been probed and analyzed from the partial perspective of single disciplines. The digital era, with its unprecedented data availability, is allowing for testing old theories and developing new ones, ultimately challenging relatively partial models. Our community has been in the last years providing more and more compelling evidence that cities are complex systems with emergent phenomena characterized by the collective behavior of their citizens who are themselves complex systems. However, more recently, it has also been shown that such multiscale complexity alone is not enough to describe some salient features of urban systems. Multilayer network modeling, accounting for both multiplexity of relationships and interdependencies among the city's subsystems, is indeed providing a novel integrated framework to study urban backbones, their resilience to unexpected perturbations due to internal or external factors, and their human flows. In this paper, we first offer an overview of the transdisciplinary efforts made to cope with the three dimensions of complexity of the city: the complexity of the urban environment, the complexity of human cognition about the city, and the complexity of city planning. In particular, we discuss how the most recent findings, for example, relating the health and wellbeing of communities to urban structure and function, from traffic congestion to distinct types of pollution, can be better understood considering a city as a multiscale and multilayer complex system. The new challenges posed by the postpandemic scenario give to this perspective an unprecedented relevance, with the necessity to address issues of reconstruction of the social fabric, recovery from prolonged psychological, social and economic stress with the ensuing mental health and wellbeing issues, and repurposing of urban organization as a consequence of new emerging practices such as massive remote working. By rethinking cities as large-scale active matter systems far from equilibrium which consume energy, process information, and adapt to the environment, we argue that enhancing social engagement, for example, involving citizens in codesigning the city and its changes in this critical postpandemic phase, can trigger widespread adoption of good practices leading to emergent effects with collective benefits which can be directly measured
New data sources to study airport competition
Full text linkTraditionally, there is a lack of detailed information
on passengers’ movements from and to the airports. This is due
to the limitations in accuracy and coverage of methodologies
like local surveys commonly used to obtain data in this context.
As a consequence, managers and policy makers must take
decisions based on partial information on passengers’ transport
demands. Recent developments and popularization of the use
of Information and Communication Technologies (ICT) provide
new alternative data-sources allowing for the precise derivation
of individual mobility at different spatial scales. This data may
pose some challenges in terms of correcting potential biases,
but it overcomes many of the traditional methods limitations.
Here, we investigate how the availability of ICT data depicts
a new comprehensive perspective on door-to-door air transport
mobility. We do this by proposing three case studies involving
three new sources of data: i) GPS records of taxi pickups; ii) a
database of geolocated tweets including 10 million users tracked
for two years in Europe; and iii) the travel-times between the
user’s home and the alternative airports (provided by Google’s
API). By integrating this data into simplified discrete choice
models, we exemplify how the description of airport catchment
areas can be treated in large cities served by more than one
airport. This works illustrates how the air transportation system
interacts with other transport modes in the passengers decision
process. While passengers can still be described within the
classical rational choice paradigm, new models must be developed
to include the influence of ground transportation aspects in the
passenger’s travel decisions
Critical behavior in interdependent spatial spreading processes with distinct characteristic time scales
Full text linkThe spread of an infectious disease is well approximated by metapopulation networks connected by human mobility flow and upon which an epidemiological model is defined. In order to account for travel restrictions or cancellation we introduce a model with a parameter that explicitly indicates the ratio between the time scales of the intervening processes. We study the critical properties of the epidemic process and its dependence on such a parameter. We find that the critical threshold separating the absorbing state from the active state depends on the scale parameter and exhibits a critical behavior itself: a metacritical point – a critical value in the curve of critical points – reflected in the behavior of the attack rate measured for a wide range of empirical metapopulation systems. Our results have potential policy implications, since they establish a non-trivial critical behavior between temporal scales of reaction (epidemic spread) and diffusion (human mobility) processes
Lost in transportation: Information measures and cognitive limits in multilayer navigation
Full text linkCities and their transportation systems become increasingly complex and multimodal as they grow, and it is natural to wonder whether it is possible to quantitatively characterize our difficulty navigating in them and whether such navigation exceeds our cognitive limits. A transition between different search strategies for navigating in metropolitan maps has been observed for large, complex metropolitan networks. This evidence suggests the existence of a limit associated with cognitive overload and caused by a large amount of information that needs to be processed. In this light, we analyzed the world's 15 largest metropolitan networks and estimated the information limit for determining a trip in a transportation system to be on the order of 8 bits. Similar to the "Dunbar number," which represents a limit to the size of an individual's friendship circle, our cognitive limit suggests that maps should not consist of more than 250 connection points to be easily readable. We also show that including connections with other transportation modes dramatically increases the information needed to navigate in multilayer transportation networks. In large cities such as New York, Paris, and Tokyo, more than 80% of the trips are above the 8-bit limit. Multimodal transportation systems in large cities have thus already exceeded human cognitive limits and, consequently, the traditional view of navigation in cities has to be revised substantially
Individual risk perception and empirical social structures shape the dynamics of infectious disease outbreaks
Full text linkThe dynamics of a spreading disease and individual behavioral changes are entangled processes that have to be addressed together in order to effectively manage an outbreak. Here, we relate individual risk perception to the adoption of a specific set of control measures, as obtained from an extensive large-scale survey performed via Facebook- involving more than 500,000 respondents from 64 countries-showing that there is a "oneto- one"relationship between perceived epidemic risk and compliance with a set of mitigation rules. We then develop a mathematical model for the spreading of a disease-sharing epidemiological features with COVID-19-that explicitly takes into account non-compliant individual behaviors and evaluates the impact of a population fraction of infectious risk-deniers on the epidemic dynamics. Our modeling study grounds on a wide set of structures, including both synthetic and more than 180 real-world contact patterns, to evaluate, in realistic scenarios, how network features typical of human interaction patterns impact the spread of a disease. In both synthetic and real contact patterns we find that epidemic spreading is hindered for decreasing population fractions of risk-denier individuals. From empirical contact patterns we demonstrate that connectivity heterogeneity and group structure significantly affect the peak of hospitalized population: Higher modularity and heterogeneity of social contacts are linked to lower peaks at a fixed fraction of risk-denier individuals while, at the same time, such features increase the relative impact on hospitalizations with respect to the case where everyone correctly perceive the risks
Correzione dell'insufficienza polmonare con homograft criopreservato: ottima soluzione ad un problema post-chirurgico non raro
No full textAlthough the results of surgical repair for congenital pulmonary stenosis are generally good, some patients develop progressive symptoms related to pulmonary regurgitation and right ventricular dilation. Pulmonary homograft implantation may have a beneficial effect on these symptoms, due to a reduction in the volume overload of the right ventricle and hemodynamic improvement. We describe our experience of one patient with severe pulmonary regurgitation following pulmonary valvotomy performed with the Brock technique during childhood because of pulmonary valve stenosis. The patient was admitted to our Institution because of dyspnea on exertion (NYHA functional class II-III) and paroxysmal episodes of supraventricular arrhythmias. Echocardiography showed severe pulmonary regurgitation, an important right ventricular dilation associated with severe tricuspid insufficiency and a patent foramen ovale without any significant shunts. Surgical repair was performed through a median sternotomy with cardiopulmonary bypass and moderate hypothermia. The right ventricular infundibulum was opened and a cryopreserved pulmonary homograft was implanted with continuous sutures. De Vega annuloplasty was performed on the tricuspid valve and the patent foramen ovale was closed with a running suture. Postoperative course was uneventful and the patient was discharged on the seventh postoperative day. Three months after surgery the patient is asymptomatic and echocardiographic evaluation shows no evidence of pulmonary or tricuspid regurgitation, a decrease in right ventricular dilation and a significant improvement in biventricular systolic and diastolic function. In conclusion, pulmonary regurgitation after surgical valvotomy can be treated with the implantation of a cryopreserved pulmonary homograft with satisfactory results. It would appear advisable to perform surgical repair of concomitant right heart anomalies, such as secondary tricuspid insufficiency, to obtain both a decrease in right ventricular overload and a regression of its preoperative dilation
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