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In this paper, authors deal with the problem of optimal location of traffic count sections and propose two new rules that aim at enhancing the reliability of the estimated O/D matrices in case of limited availability of sections to be located. These rules are tested on a real size extra-urban road network and are compared to a state-of-the art rule that is widely used in practical applications.

Traffic assignment is a set of criteria through which the demand for mobility is distributed over the links of a transport network. Over the last 30 years, Dynamic Traffic Assignment (DTA) models have been developed to support time-dependent analyses in nascent fields that need to take into account the temporal distribution of demand and supply. In this book, leading international experts in the field provide a state-of-the-art overview of fundamental DTA research and practice, identifying weaknesses and major challenges for future research.

This paper investigates the problem of the network performance forecast by using traffic data acquired via Bluetooth devices in order to provide advanced models and tools for the prediction of congestion effects in urban areas. A data driven approach is adopted where different statistical models are tested within a methodology framework in which the above data are filtered, cleaned and fused for a better prediction of path travel times. The proposed approach has been applied to the city of Rome: performances that better fit observed traffic conditions have been obtained by adopting an ARIMA based model whose promising results of online forecast are presented and discussed.

Travel time information is gaining increasing importance as traffic performance measure from the perspective of both drivers to understand traffic conditions and network management to properly monitor and control the evolution of traffic conditions. Aiming at forecasting path travel times in congested urban areas, this paper proposes a data- driven approach in which traffic data are collected via Bluetooth and mobile Floating Car Data devices. Such data are used to improve the accuracy of the detected information by means of a Gaussian Mixture Model (GMM) and a Bayesian data fusion approach. The GMM is applied to estimate the travel time and not only its distribution and it is calibrated for each time interval and updated with every available data on real time. An Auto- Regressive Integrated Moving Average model is used for the travel time forecast. An application to a real-life test case in the city of Rome shows the goodness of the proposed approach for better online network performance forecast.

Dealing with emergencies is never an easy task. Coping with the Covid-19 emergency was and still is an incredibly tough and unprecedent challenge for mankind, not only from a healthy point of view, but also from a socio-economic point of view, where a key role will be played by a reliable and sustainable transport of people and goods. Professional and researchers from all disciplines have been required to adapt their models, methods and tools to support decision makers in coronavirus emergency days. This paper reports the experience of the authors for the analysis of the Rome mobility system to estimate the impacts of the progressive lockdown imposed by the government. It focuses on data available for monitoring, which have been used to carry out transport analytics both for private and public transport. Such analytics have been used for planning the reboot of the transport system to be ready for the post Covid-19 era.

In this paper, a single-chip front-end (SCFE) operating in Ku-band (12–17 GHz) is presented. It is designed exploiting a GaN on SiC technology featured by 150 nm gate length provided by UMS foundry. This MMIC integrates high power and low noise amplification functions enabled by a single-pole double-throw (SPDT) switch, occupying a total area of 20 mm2. The transmitting chain (Tx) presents a 39 dBm output power, a power added efficiency (PAE) higher than 30% and a 22 dB power gain. The receive path (Rx) offers a low noise figure (NF) lower than 2.8 dB with 25 dB of linear gain. The Rx port output power leakage is limited on chip to be below 15 dBm even at high compression levels. Finally, a complete characterization of the SCFE in the Rx and Tx modes is presented, also showing the measurement of the recovery time in the presence of large-signal interferences.

Aiming at supporting decision makers in transport policy choices, transport models used for decades the trip-based approach for travel demand forecasts. This approach, despite suited to peak hours modelling where systematic trips are predominant, suffers the limits of not being related to the sequence of activities usually undertaken in real day-life. Differently, in the Activity Based Models (ABM) the travel demand is explicitly modelled as the result of individuals’ involvement in different activities in different times and locations. The use of such models is recommended when complex trip chains connected to the multiple daily activities that characterise today's life have to be taken into account, even if the integration with other sub-models (particularly with the assignment) within the whole transport modelling procedure has to be carefully considered. For this reason, this paper focuses on the integration between ABM and transport assignment by investigating the multimodal demand-supply interaction. Specifically, the consistency between ABM and assignment models is studied proposing a methodology that can be applied to large real size networks. It is based on a multimodal static equilibrium assignment, which is easy-to-use and less time consuming with respect to a Dynamic Traffic Assignment (DTA), allowing a better estimation of the modal splits between alternative transport modes. Such a model also considers (road) congestion and (transit) crowding phenomena, as well as the multimodal network performances are estimated by taking into account the interaction between different modes sharing the same network facilities. The goodness of the proposed approach is investigated through the convergence analysis of both the entire integration procedure and its individual components (ABM and assignment) for a better transport simulation in urban areas. The application to an urban multimodal network of real-size dimensions (Rome) is presented to show the promising results of this research.

The Southern Quarter of Velia represents a particularly stimulating case-study concerning the relationship between settlement and environment. The lower city, indeed, is affected, especially in the Imperial age, by a series of alluvial floods, that gradually modify the inhabited area layout, determining the walking surfaces aggradation and various rearrangement buildings interventions. Recent research data offers the first elements to discuss the impact of these events on the community and its resilience capacity. The ceramic assemblage from the sampled area returned data for the formation processes interpretation and chronological reconstruction of the context. The different approaches (quantitative, qualitative, chronological and spatial analysis) allowed to recognize the impact of the alluvial events on the stratigraphical sequence. The chrono-typological evaluation enabled a preliminary reconstruction of the Middle and Late Roman ceramic repertoires, a phase still not so known in Velia.

Aiming at supporting decision makers in transport policy choices in an increasingly complex sequence of activities of our real day-life, this paper investigates the integration between Activity Based Model (ABM) and transport assignment by focusing on the multimodal demand-supply interaction to be used in more advanced simulation models. The consistency between ABM and assignment models is studied proposing a methodology that can be applied to large real size networks. A new formalization of integration of ABM with multimodal assignment is proposed, oriented to an easy-to-use and computationally faster application. The interaction between different modes sharing the same network facilities is considered, as well as crowding (public transport) and congestion (road) phenomena. The application to different real case studies in Qatar and in Rome are presented to show the promising results of the proposed approach for a better transport simulation in urban areas.

During the Greek period the Cyrenean Sanctuary of Apollo Pizius has been expanding to the E (Garden of Aphrodite), to the S (Spring Terrace, previously external to the temenos) and to the W (Alsos of Apollo and Theatre). During the age of Battiades a unitary project took place in order to monumentalize the sacred area on the model of the Panhellenic sanctuaries of Olympia, Delphi and Delos. With the fall of the monarchy, works of urban impact were realized with the aim of delimiting and rationally organizing the sacred space. In this phase, the lower strata of the community gain power, emphasizing cults previously not documented by monumental remains. In the 4th century BC the temenos reaches his final limits, but with a gradual loss of the previous organicity, due to the construction of new sacred, celebratory and utilitarian buildings, which reflect the new needs of the ruling class. In the Hellenistic period, the structure of the sanctuary underwent radical transformations, with a multiplication of the monuments linked to the further increase in the political significance of the cult of Apollo, connected with the post-Alexandrian dynastic ideology, according to a polycentric conception of cultural activities that will characterize the complex until the end of his life.

The paper describes research activities of monitoring, modeling, and planning of people mobility in Rome during the Covid-19 epidemic period from March to June 2020. The results of data collection for different transport modes (walking, bicycle, car, and transit) are presented and analyzed. A specific focus is provided for the subway mass transit, where 1 m interpersonal distancing is required to prevent the risks for Covid-19 contagion together with the use of masks and gloves. A transport system model has been calibrated on the data collected during the lockdown period –when people's behavior significantly changed because of smart-working adoption and contagion fear– and was applied to predict future mobility scenarios under different assumptions on economic activities restarting. Based on the estimations of passenger loading, a timing policy that differentiates the opening hours of the shops depending on their commercial category was implemented, and an additional bus transit service was introduced to avoid incompatible loads of the subway lines with the required interpersonal distancing.

Recent advances in technology have made available numerous new monitoring systems that collect updated traffic measurements both in fixed locations and over specific corridors or paths. Such recent technological developments point to challenging and promising opportunities for Origin-Destination (OD) traffic demand estimation and forecast. Therefore, the aim of this paper is to study how to exploit available information detected by new monitoring devices in the estimation of traffic demand. Starting from the formulation proposed by Spiess (1987, 1990), in this paper a new method to estimate the traffic demand by means of Bluetooth data is proposed. It explores inherent properties of this information in an off-line (and static) context, where mathematical formulation of the estimation problem can be derived. The effectiveness of the proposed method has been investigated in an extensive plan of experiments carried out both on test networks and on a study network consisting in a part of the city of Rome, Italy, obtaining promising results in both applications.

This paper presents the results of a study on the Rome mobility system aiming at estimating the impacts of the progressive lockdown, imposed by the government, due to the Covid-19 pandemic as well as to support decision makers in planning the transport system for the restart towards a post-Covid “new normal”. The analysis of data obtained by the transport monitoring system has been fundamental for both investigating effects of the lockdown and feeding transport models to predict the impacts on future actions. At first, the paper focuses on the so-called transport analytics, by describing mobility trends for the multimodal transportation system of Rome. Then, the results of the simulated scenarios to design public transport services, able to ensure passengers social distancing required in the first post-Covid months, are presented and discussed.

Carsharing is a car rental system in which members have access to a fleet of cars on a relatively short time basis. Several different types of car-sharing services have been developed such as round-Trip and free-floating: The first one is characterized by a more rigid structure because of its station-based nature, the second tends to be more flexible since a customer can pick up and drop off the car in any public parking inside a wide area. Being a member is the first step users have to take to use this sharing service. This study focuses on the analysis of supply attributes directly linked to territorial characteristics such as parking availability, parking price, distance from the city center, users' trip chain in relation with location of activities and their impact on the membership choice. By using a binary logit model, and a synthetic population of the city of Berlin representing members of both the round-Trip and the free-floating service, and through a sensitivity analysis, the study shows how membership is sensible to some of these attributes identifying which supply characteristics impact the user membership choice. Results suggest there are two typical membership profiles and the attributes that lead the choice are different. While a round-Trip carsharing member is more willing to drive towards more than one destination and does not always have his/her own car available, the free-floating carsharing member is more apt to use a point-To-point trip scheme driving for more than 15 minutes using the service as substitute of the owned car.

Sharing Mobility is characterized by a high digital component able to supply customers with a considerable level of flexibility in urban trips. The study was conducted focusing on the E-go car sharing project, promoted by University of Roma Tre and Enel Energia S.p.A. E-go is an university electric car sharing system. The paper provides a double contribution to the research activity on sharing mobility: i) the exploration of the electric car sharing potential demand among students; ii) the implementation of an Hybrid Choice Model to analyze the role of the pro-environmental attitude on the users’ willingness to use car sharing. The analysis has been based on the data collected in a survey among the potential users of the e-go car sharing service. One of the first findings of the study is that the pro-environmental attitude doesn’t significantly influence the choice of the users. The authors suggest to the car sharing operators and to the policy makers to take in consideration the results of the study in order to plan promotional strategies and to develop policies aiming at supporting the spread of this service.

Tomb 713 from the Valle Trebba necropolis of Spina is a female burial belonging to a group of graves which stands out by the exceptional character of the grave goods and the specific ideological choices expressed by the objects. Within the Tomb, the presence of a red-figured kyathos with unique characteristics leads to a study of its hypothetical manufacturing process and its functional, cultural and ideological implications in the burial context.

Increasing sustainability of urban transport systems is a crucial objective of all strategic plans both at national and European level. Different strategies and measures can be adopted to improve the efficiency of transport systems, according to a large set of factors that can affect the results of the implemented actions. A comprehensive study has been carried out in order to define a methodology able to define effective and efficient strategies and measures, allowing to increase the sustainability level of different kinds of cities, from small-medium sized to large metropolitan areas. The methodology has been tested on a group of 50 Italian cities, whose characteristics have been analysed through an initial set of more than 200 indicators. Three main groups of indicators have been taken into account: State indicators, Sustainability indicators, Policy indicators. The main aim has been to identify existing relationships between Sustainability and Policy indicators for cities showing commonalities in terms of State indicators. A correlation analysis allowed to identify 53 relevant indicators from the initial set of 200, while a cluster analysis, based on a hierarchical model, allowed to group the cities into five different groups, according to their population size and density. Correlations between relevant indicators have also been analysed within each group, while linear regression models have allowed to describe some functional relations between Policy and Sustainability indicators. A benchmarking exercise has allowed to identify strategies and measures adopted by the best performers within each group, hence defining possible paths to a better sustainability level for the remaining cities. Finally, recommendations for a correct urban mobility planning procedures have been produced.

Starting from the mathematical bases of waveform engineering, this contribution demonstrates the effectiveness of class-F power amplifier design in different bias conditions, provided the correct harmonic content is presented at the input. To validate the theoretical assumptions, low-frequency multi-harmonic load-pull measurements are carried out on a 1-mm gate periphery GaN HEMT, giving an experimental proof of the validity of the extended harmonic manipulation approach.

This paper focuses on modelling on-street parking search time by using FCD data coming from probe vehicles. It is based on data detected by probe vehicles, which allow to identify the typical spiral around the destination that vehicles perform in the final part of the trip to find a parking place. The proposed model is suitable to be used either in real-time to support user information and dynamic routing, or off-line for a better assessment of transport plans. A real-size application to the city of Rome is presented to show the promising results obtained for the estimation of parking search time in urban areas.

The purpose of this invited paper is to give readers a comprehensive and critical overview on how to extract equivalent-circuit models for GaN HEMTs, which are the preferred devices for high-power high-frequency applications. This overview is meant to provide a practical modeling know-how for this advanced type of transistor, in order to support its development for improving device technology and circuit design. With the aim to broaden knowledge to empower models, experimental results are presented as illustrative examples of the most crucial challenges faced by the microwave engineers in modeling high-power GaN HEMTs. All the relevant aspects are covered, going from linear (also noise) to nonlinear models. The analysis is mainly focused on the modeling of distinctive peculiarities of GaN HEMTs. Particular attention is paid to study the importance of accurately modeling the kink effect in the output reflection coefficient, because of the relatively high transconductance, the peak in the magnitude of the short circuit current-gain, because of the relatively large intrinsic capacitances, and the low-frequency dispersion, because of trapping and thermal effects. Furthermore, to emphasize the key role of accurate device models for a successful circuit design, a practical example of power amplifier is discussed.

This contribution aims at the experimental confirmation of the advantages of the harmonic manipulation theory, using a low-frequency low-cost characterization setup. A 0.5-μm 10x100-μm (1-mm gate periphery) GaN HEMT has been characterized synthesizing at the current-generator plane different load conditions, realizing tuned-load and Class-F operation. The measurements clearly demonstrate the importance of by synthesizing the required loads at the correct reference plane, giving an experimental proof of the performance predicted by theoretical analysis. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.

The present contribution summarizes the activities performed towards the realization of a Single-Chip Front-End (SCFE) operating in C Band, integrating the High Power, Low Noise amplification and switching functionalities to be provided in modern T/R modules' Front-Ends for space SAR applications. The technologies adopted in this project are provided by United Monolithic Semiconductors (UMS) and Selex Electronic Systems (SLX), the GH25-10 0.25 µm gate length and the GaN technology featured by 0.5 µm gate length for UMS and SLX respectively. At the completion of the design phase two SCFEs have been designed in the two technologies, each in two slightly different versions, featured by state-of-the-art performance. In particular, in Tx-mode, both are featured by approximately 40 W power output, with 36 dB large-signal gain and 38 % / 27 % PAE for UMS and SLX versions respectively, while in Rx-mode 2.5 dB noise figure resulted, with robust operation. The two dies are featured by 6.9 × 5.4 mm2 and 7.28 × 5.40 mm2 for UMS and SLX versions respectively.

In this work, the design of a C-band class-AB power amplifier based on the waveform engineering approach is presented. The design leverages the low-frequency characterization of the transistor to obtain the prediction of its optimum operating condition. An exhaustive validation of the realized amplifier fully validates the proposed design technique.

In this paper, authors report a procedure to forecast the route travel time, based on different advanced traffic data, both historical and current. The procedure is articulated in two main steps: the first consists in apportioning current route travel time among the links based on historical Floating Car Data; in second step, the obtained link travel times are combined with the current loop detectors data through the measurement data fusion technique; moreover, the Extended Kalman Filter (EKF) correction is applied to a second order traffic model, in order to forecast the link speeds and consequently link and route travel times. Real applications of the proposed procedure concerning both a signalized route of Lungotevere and 6.5 kilometers urban freeway with 14 on/off-ramps in Rome are reported. The results of the forecasted route travel time show a good accuracy until the detected data used to correct the estimation are coherent and the input data, such as flows on ramps, are reliable. The results of the link speeds in terms of RMSE and RME with respect to the data detected by the loop sensors seem to be accurate, however further development will deal with the comparison to the other existing methods. Finally, the results underline, as it is well known, the need of real and reliable data in order to provide a good forecast.

In this research we describe the development of a common evaluation and benchmarking platform that has been developed within the framework of the European Union COST Action MULTITUDE. The main goal of this platform is to provide a testbed in which a number of algorithms can be implemented and tested under the same conditions. The objective is not to conclude that one approach is “best”, but to provide a support comparison in a variety of settings and conditions in order to help determine the particular situations and conditions under which one approach might behave more favorably than another. The design of the platform is presented, along with a detailed experimental design for the application of different OD estimation algorithms. The considered algorithms are then presented, along with a demonstration of the extensibility of the presented framework to accommodate additional data sources. The presented results demonstrate that the developed framework is capable of supporting the development, application and testing of a wide range of algorithms. First, both off-line/planning level algorithms (like the Bilevel-DUE) and on-line algorithms (like that SPSA AD-PI and the KFX2) are presented.

In this paper a characterization technique for the evaluation of transistor performance and restrictions is presented, based on a simple and low-cost measurement system. Experimental examples, carried out on a 0.5 × 1000 μm2GaN HEMT, are reported. The validity of the proposed approach is demonstrated by comparing the results with the ones obtained by means of commonly adopted measurement setups.

There have always been arguments between airports and local communities because of the aeronautical noise. In fact, this is a factor that, if not properly managed, can severely cut down the development of air traffic in an airport with direct repercussions on the economic and territorial system. Nevertheless, particularly in the last decade, the critical issues relating to the impact of aeronautical noise on airport operations have greatly reduced thanks to the technological improvements in the design of aircrafts. However, the reduction of the noise emission during a single event does not make the issue of the airports’ location less important. This is the case of regional airports that have recently experimented a large traffic increase due to the development of low-cost traffic. It is now clear that the problem can not be reduced to its mere technological aspects, but it ought to be dealt with the involvement of the various entities in order to mitigate the impacts and adequately compensate the damages to local communities. Typically, there are two possible countermeasures to mitigate the effects of aircraft noise: operational measures, based on the application of technological and organizational devices and market-based measures. For example, the application of noise taxes or noise charges aiming at compensating the negative externalities generated by airport operations is becoming increasingly widespread. This paper discusses a methodology for the application of noise taxes based on the actual noise of aircraft operating into an airport.

This paper describes the implementation in Palermo of a new approach developed at Newcastle University (UK), in the context of the MESSAGE project (Mobile Environmental Sensing System Across Grid Environments), using a novel inexpensive pervasive sensor system. The new system infrastructure shows how additional data from the new environmental sensors, namely “mote” can improve the assessment of the impact of traffic and congestion on air quality. After an evaluation and validation process of the sensors against the precision system (City Council Environmental Cabin) the sensors where deployed in Palermo and using the data, actual traffic flows and pedestrian traffic light information (all synchronised at one minute resolution), a simulation model was set up to predict air quality, and potentially noise and exposure levels for pedestrian. The proposed approach has been evaluated using a case study area in Palermo, namely a street canyon, in Libertà Avenue. Analysis, calibration and validation of data from two static pervasive sensors, will be presented in this paper. Next the process by which the traffic characteristics (fleet composition, flow, queue length) collected over two months survey were used to validate parameters of the AIMSUN traffic simulation model (flows, queues, congestion states) will be shown. The validated microsimulation model subsequently was used to predict tailpipe emissions taking into account the traffic flow regimes (free flow, unstable and congested) and pollution concentrations which were estimated within the street canyon using the OSPM (Operational Street Pollution Model) model.These estimates will be compared with the pervasive sensor measurements of air pollution, CO, Carbon Monoxide and NO2, Nitrogen dioxide. Results presented in this paper will highlight the benefits of pervasive sensors in the model validation and how they can compliment legacy systems through their flexibility in covering detection gaps in existing urban networks. Moreover, the proposed approach will have the capacity to assess the changes caused in previously unmonitored areas, resulting in more realistic assessments of the impacts of transport policies and strategies. Finally, an evaluation of emissions impact from new pedestrian traffic light scenarios is presented.

To the Editor: Nonvalvular atrial fibrillation (NVAF) is the most common sustained arrhythmia encountered in clinical practice and is associated with a 5-fold increased risk for stroke (1). Moreover, patients with NVAF often suffer from atherosclerotic complications such as acute myocardial infarction (AMI) (2). Peripheral artery disease (PAD) is an established marker of systemic atherosclerosis but its prevalence in NVAF is still unclear. We reasoned that inclusion of ankle-brachial index (ABI), which is an established tool for diagnosis of PAD (3), in the CHA2DS2-VASc (4) score would better define the prevalence of vascular disease. To address this issue, the Italian Society of Internal Medicine (SIMI) established an Italian registry documenting ABI in NVAF patients. The Atrial Fibrillation Registry for the ARAPACIS (Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study) study is an independent research project involving all Regional Councils of SIMI. The first objective of the study was to estimate the prevalence of ABI ≤0.90 in NVAF patients. Consecutive patients with NVAF referred to internal medicine wards were eligible for the enrollment. Enrollment started in October 2010 and continued until October 30, 2012. Patients were enrolled if they were 18 years or older and had a diagnosis of NVAF, recording during the qualifying admission/consultation or in the preceding 12 months, and if it was possible to obtain the ABI measurement. Exclusion criteria included the following: acquired or congenital valvular AF, active cancer, disease with life expectancy 0.90 (93% vs. 82%; p < 0.0001). Logistic regression analysis demonstrated that ABI ≤0.90 was significantly associated with a smoking habit (odds ratio [OR]: 1.99; 95% confidence interval [CI]: 1.48 to 2.66; p < 0.0001), diabetes (OR: 1.93; 95% CI: 1.51 to 2.46; p < 0.0001), age class 65 to 74 years (OR: 2.05; 95% CI: 1.40 to 3.07; p < 0.0001), age class ≥75 years (OR: 3.12; 95% CI: 2.16 to 4.61; p < 0.0001), and history of previous transient ischemic attack/stroke (OR: 1.64; 95% CI: 1.20 to 2.24; p = 0.002). Vascular disease, as assessed by the history elements of CHA2DS2VASc score, was recorded in 17.3% of patients; inclusion of ABI ≤0.90 in the definition of vascular disease yielded a total prevalence of 33%. A higher prevalence of vascular disease was detected if ABI ≤0.90 was included in the CHA2DS2VASc score (Fig. 1). CHA2DS2VASc including ABI ≤0.90 was more associated with previous stroke (43%; OR: 1.85; 95% CI: 1.41 to 2.44; p < 0.0001) compared to CHA2DS2VASc with ABI 0.91 to 1.39 (23%; OR: 1.52; 95% CI: 1.10 to 2.11; p = 0.0117). To the best of our knowledge, there is no large-scale study that specifically examined the prevalence of ABI ≤0.90 in NVAF. In our population, 21% had ABI ≤0.90 indicating that NVAF is often associated with systemic atherosclerosis. The CHADS2 has been recently refined with the CHA2DS2-VASc score, which includes vascular disease as documented by a history of AMI, symptomatic PAD, or detection of atherosclerotic plaque in the aortic arch (4). Comparison of vascular prevalence as assessed by CHA2DS2-VASc score and/or ABI ≤0.90 is of interest to define the potentially positive impact of measuring ABI in the management of NVAF patients. Inclusion of ABI ≤0.90 in the definition of vascular disease greatly increased the prevalence of vascular disease, which increased from 17.3% (based on history alone) to 33% (based on ABI) in the entire population. If ABI ≤0.90 was encompassed in the definition of vascular disease of CHA2DS2-VASc score the prevalence of vascular disease increased in every risk class. Inclusion of ABI ≤0.90 in the CHA2DS2-VASc score allowed us to better define the risk profile of NVAF patients with an up-grading of the risk score in each CHA2DS2-VASc score category. This may have important therapeutic implications if the new score could be tested prospectively, as a higher number of NVAF patients would potentially be candidates for an anticoagulant treatment by measuring ABI. A prospective study is, therefore, necessary to validate the risk score of this new definition of vascular disease. In conclusion, this study provides the first evidence that one-fifth of NVAF patients had an ABI ≤0.90, indicating that it may represent a simple and cheap method to better define the prevalence of vascular disease in NVAF.