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Background: Information about the adherence to scientific societies guidelines in the ‘real-world’ therapeutic management of oncological patients are lacking. This multicenter, prospective survey was aimed to improve the knowledge relative to 2017-2018 recommendations of the Italian Association of Medical Oncology (AIOM). Patients and methods: Treatment-naive adult patients with pancreatic adenocarcinoma were enrolled. Group A received adjuvant therapy, group B received primary chemotherapy, and group C had metastatic disease. The results on patients accrued until 31 October 2019 with a mature follow-up were presented. Results: Since July 2017, 833 eligible patients of 923 (90%) were enrolled in 44 Italian centers. The median age was 69 years (range 36-89 years; 24% >75 years); 48% were female; 93% had Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1; group A: 16%, group B: 30%; group C: 54%; 72% Nord, 13% Center, 15% South. In group A, guidelines adherence was 68% [95% confidence interval (CI) 59% to 76%]; 53% of patients received gemcitabine and 15% gemcitabine þ capecitabine; median CA19.9 was 29 (range 0-7300; not reported 15%); median survival was 36.4 months (95% CI 27.5-47.3 months). In group B, guidelines adherence was 96% (95% CI 92% to 98%); 55% of patients received nab-paclitaxel þ gemcitabine, 27% FOLFIRINOX, 12% gemcitabine, and 3% clinical trial; median CA19.9 was 337 (range 0-20220; not reported 9%); median survival was 18.1 months (95% CI 15.6-19.9 months). In group C, guidelines adherence was 96% (95% CI 94% to 98%); 71% of patients received nabpaclitaxel þ gemcitabine, 16% gemcitabine, 8% FOLFIRINOX, and 4% clinical trial; liver and lung metastases were reported in 76% and 23% of patients, respectively; median CA19.9 value was 760 (range 0-1374500; not reported 9%); median survival was 10.0 months (95% CI 9.1-11.1 months). Conclusions: The GARIBALDI survey shows a very high rate of adherence to guidelines and survival outcome in line with the literature. CA19.9 testing should be enhanced; nutritional and psychological counseling represent an unmet need. Enrollment to assess adherence to updated AIOM guidelines is ongoing.

Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder with multisystemic involvement, affecting central nervous system, skin, bone system and vessels, with a very heterogeneous clinical presentation. Vascular abnormalities are typically recognized in neurofibromatosis type 1 affecting cardiovascular and cerebrovascular systems. The incidence of circle of Willis anomalies in children with NF1 is twofold higher than in general population. In this paper, we report of 19-years-old female with NF1 and twig-like middle cerebral artery.

Minimally invasive vertebral augmentation procedures (VAP) have been first introduced to provide pain relief in patients with osteoporotic vertebral fractures (VF). However, in the last decade scientific literature revealed to be quite controversial about their efficacy. The aim of this review was to analyze clinical evidences from current literature, supported by our own experience. Compared to conservative therapies, VAP represent an effective treatment for recent VF and, in elderly patients, reduce mortality and morbidity. Advances in technology have widened the fields of application towards other spine pathologies typical of elderly, such as primary and metastatic tumors. In patients with severe pain for recent or un-healed vertebral fracture, VAP are clinically more effective than conservative treatment. Accurate pain assessment and pre-procedural Magnetic Resonance Imaging are highly recommended to obtain optimal patient selection and best treatment results.

The paper presents a novel algorithm based on a change-detection approach to localize nodes moving in a bounded region where the transversal direction has much more limited extent compared to the longitudinal one (e.g., roads, rails, corridors, etc.). The proposed method allows a mobile node to detect the time instant it crosses a radiofrequency source, either fixed or mobile, that transmits a signal of opportunity. The detection is based on a generalized likelihood ratio test (GLRT) aimed at discriminating whether the angle-of-arrival (AOA) estimates obtained from such signal are significantly different from zero or not. The detected crossing events can be then used by the mobile node to improve the accuracy of its position estimate. Simulation results are provided for a realistic application scenario, which demonstrate that the proposed algorithm can achieve satisfactory localization performance with low computational complexity, thus representing a possible alternative to state-of-art position estimation methods in transversally-bounded localization domains.

The limited localization capabilities provided by global navigation satellite systems (GNSS) is one of the main obstacles toward the development of reliable road safety applications in urban scenarios. In order to improve GNSS accuracy, a number of approaches have been proposed which exploit additional position-related information, for instance provided by local inertial sensors. However, such solutions cannot meet the very stringent accuracy requirements of safety applications, which call for advanced processing and the fusion of position-related signals and data from heterogeneous sources. In this paper, we aim at combining the potential of antenna array processing with a suitably-designed cooperation strategy that exploits vehicle-to-vehicle and vehicle-to-infrastructure communications. Particularly, we define a novel tracking algorithm with asynchronous updates triggered by beacon packet receptions, from which angle of arrival estimates are opportunistically obtained. A dynamic setting of relevant parameters allows the resulting cooperative positioning algorithm to adapt to the different operating conditions found in urban vehicular contexts. Simulation results under realistic environment conditions show that the proposed algorithm can achieve high position accuracy even in sparse scenarios, outperforming a natural competitor while keeping lightweight communication and low computational complexity.

BACKGROUND AND AIMS: Conventional surgery of the thoracic aorta is frequently associated with significant mortality and morbidity. Here we present treatment of surgical pathologies of the thoracic aorta using a less invasive endovascular approach. METHODS: From January 2000 to May 2004, 51 patients (mean age 62.7 +/- 12.8 years, 36 men) underwent endovascular repair of thoracic aortic lesions in our institution. All patients underwent computed tomography scan at discharge, 6 and 12 months and annually thereafter. Clinical follow-up was carried out by outpatient clinic visit or by telephone contact with the patients or their referring physicians. Mean follow-up was 15.8 months. RESULTS: The 30-day mortality rate was 3.8%, one death in the group of chronic (1.9%) and one in the group of acute lesion (1.9%). The survival rate in the follow-up period was 92.4% at 6 months. Computed tomography angiography confirmed exclusion of the lesion in 25 out of 27 chronic patients, whereas type I and II endoleaks were detected in two patients treated with a secondary procedure. In addition, two patients with an acute type B aortic dissection presented with early endoleaks. The overall rate of complications was 10%. No other endoleaks or deaths were observed at later follow-up. CONCLUSIONS: The early and mid-term results of endovascular stent-grafting for the treatment of chronic and acute thoracic aortic diseases showed a good outcome and low rate of complications. Stent-grafting of the thoracic aorta is still an investigational procedure that needs further validation.

This paper addresses vehicle positioning based on TDOA ranging for an infrastructured scenario. In particular, a mobile vehicle can determine its current position by combining TDOA measurements collected from a certain number of road side units. At the design stage the road side units are assumed to be synchronized, but the effects of synchronization errors are taken into account at the analysis stage. The performance assessment shows that the proposed approach can outperform a GPS receiver typically available for the automotive market.

This paper proposes an algorithm to be used in IEEE 802.16e networks for adapting MAC PDU size to wireless channel behavior when ARQ is adopted at MAC layer. The algorithm is based on an analytical approach for dynamically evaluating the optimal packet size. The latter is derived from an expression of the ARQ protocol efficiency, obtained by exploiting a finite-state Markov error model which also takes into account Adaptive Modulation/Coding. The effectiveness of the designed algorithm in improving TCP performance has been evaluated.

A number of Intelligent Flooding Schemes have been recently proposed to optimize message dissemination in Vehicular Ad Hoc Networks. Some of them exploit a distributed timer-based contention mechanism in order to allow the most suitable nodes to forward the packet and to suppress other potential forwarders. Unfortunately, due to some problems related to the suppression mechanism, most of these schemes are not able to completely avoid useless copies of the message to be broadcast. Moreover, in many cases, the contention mechanism determines when the message has to be rebroadcast, thus thwarting the application in processing the message. The use of MAC layer control packet handshake allows to mitigate the issues above, but it could lead to an unacceptable overhead and to a high probability of dissemination interruption. In this paper we propose a new scheme, called Data-Ack Scheme (DAS), which operates at MAC layer. It allows to reduce the overhead by using one only control packet and makes the dissemination interruption most unlikely. Simulation results have shown that in a typical vehicular scenario DAS performance is better than that obtained when either a MAC layer handshake-based scheme or a scheme which does not provide the use of control packets is adopted.

A number of Intelligent Flooding Schemes have been recently proposed in order to optimize message dissemination in Vehicular Ad Hoc Networks. In this paper we focus on a scheme which exploits a distributed timer-based contention mechanism for allowing only contention winners to forward the message and to suppress other potential forwarders. In particular, at each hop along the message propagation direction, potential forwarders wait for a time which is inversely proportional to their distance from the sender before rebroadcasting the packet; a potential forwarder is suppressed if it intercepts the packet rebroadcasted by another node during the waiting time. Performance of the scheme, in terms of message delivery ratio, delay and channel utilization, depends on the maximum waiting time (MaxWT) and on the maximum distance R allowed between the sender and a potential forwarder. This research work aims at evaluating an optimal setting of these parameters. We show that, although the values of MaxWT and R which maximize performance vary with traffic load and vehicle density, a dynamic algorithm is not essential. Then, we report how to set the values of the parameters to achieve a performance that is acceptable in the scenarios which we have considered.

Broadcasting will be extensively used in Vehicular Ad Hoc Networks (VANET), mainly for spreading out safety messages. A number of Intelligent Flooding Schemes (IFSs) have been recently proposed to optimize message dissemination. Some of them exploit a distributed timer-based contention mechanism in order to allow the most suitable nodes to forward the packet and to suppress other potential forwarders. This paper deals with those schemes which are based on a handshake similar to RTS/CTS. This helps in avoiding potential forwarders, which should be suppressed, to uselessly rebroadcast a data packet. We aimed at identifying main problems which these schemes may encounter in optimizing message dissemination. To this objective, an analysis of the events which can cause the failure of the forwarding election procedure has been carried out. The analysis has also been the starting point for devising some different design choices.

Recently, there has been much effort to integrate heterogeneous wireless technologies in order to make overlay networks able to provide mobile users with ubiquitous Internet access. Handover management is still one of the most challenging issues to be solved for seamless integration of wireless networks. In this paper, an algorithm for vertical handover with QoS guarantees between IEEE 802.16e and IEEE 802.11e networks, without computational complexity added on mobile nodes, has been proposed. It uses a decision mechanism based on the following metrics: the available bandwidth, the signal-to-noise ratio (SNR) and the access delay. Its characteristics are perfectly compatible with the guidelines specified in the IEEE 802.21 standard. The effectiveness of the defined algorithm has been evaluated, using the ns-2 tool, in terms of packet loss rate (PLR), satisfaction of minimum applications requirements and number of useless handovers. The performance of the defined algorithm has been compared with that obtained by using the algorithm suggested by IEEE 802.21 standard that exploits only the SNR in the decision procedure.

In this paper, a packet size control algorithm, fully compliant with the IEEE 802.16e standard, has been proposed. This algorithm aims to optimize the performance of a data link ARQ protocol, trying to evaluate dynamically the packet size that maximizes the mean advancement of the sender window. It offers the possibility to maximize system throughput in every mobile scenario, even in presence of wireless time-variant channels. The effectiveness of the defined algorithm has been evaluated, through computer simulation, in terms of normalized TCP goodput. Simulation results have shown that the dynamic choice of the packet size plays an important role in maximizing TCP performance.

In this paper a protocol, local to the satellite link, is defined in order to boost TCP performance in mobile integrated wired-satellite Internet. It has been conceived to help to overcome the well known retransmissions competition problem that arises when a satellite reliable link layer protocol is used to face satellite link errors. This protocol, called Local IPSec-aware Freezing proTocol (LIFT), has been designed to allow the satellite gateway, even in the presence of communications secured by IPSec, to freeze the TCP sender when it perceives a possible delay due to satellite channel conditions. The effectiveness of LIFT has been evaluated, using the ns-2 tool, in terms of Web page download mean time for a satellite mobile host. Simulation results have shown that the adoption of LIFT protocol provides substantial improvements in TCP performance.

Mobile computing and security in Internet have become two of the most important challenges in the Information Technology world. Among wireless technologies which support user mobility, satellites will play a very important role. Unfortunately, TCP does not perform well on satellite channels because of the related high delay-bandwidth product, high bit error rate (BER) and burst errors mainly due to shadowing. In order to obtain improvements in TCP performance, an approach local to the satellite link could be adopted. In fact, recently, some studies showed the effectiveness of the use of a reliable data link protocol that is well suited to mobile geo-stationary satellite channel characteristics. However, the resultant more variable end-to-end delay causes, as a side effect, a new problem: the competition between retransmission mechanisms at transport layer and data link layer. The introduction of a suitable Performance Enhancing Proxy (PEP) on the satellite gateway has proved to be a viable technique to face the problem. However, the compatibility with the usage of network layer security mechanisms, such as IPSec, should be pursued. This paper just deals with the definition of an IPSec-aware TCP PEP, called Secure PEP (SPEP), that is completely transparent to IPSec architecture. The performances of SPEP have been validated in the context of Web application by using Network Simulator tool. The simulation results, in terms of web-page download mean time, have shown that the proposed solution provides substantial improvements in TCP performance.

Integration between satellite and terrestrial networks is to play a very important role in the creation of a Global Internet which supports user mobility. Unfortunately, in these scenarios, TCP protocol tends to perform poorly because of high delay-bandwidth product, high bit error rate (BER) and burst errors mainly due to shadowing. The use of a reliable data link protocol, well suited to mobile geostationary satellite channel characteristics, can improve TCP performance appreciably. However, introducing a more variable end-to-end delay causes, as a side effect, a new problem: the competition between retransmission mechanisms at transport layer and data link layer. In order to solve this problem a TCP Performance Enhancing Proxy has been defined and validated. The simulation results, in terms or webpage download mean time, have shown that a local approach results in substantial improvements in HTTP performance, solving the retransmission competition problem.

In this paper, aiming to overcome the problems related to mobility in a Satellite Internet scenario, the data link reliable transmission over a mobile geo-stationary satellite link has been analysed. In such environment, the Selective Repeat (SR) classical version does not perform well due to high BER values and burst errors. In order to cope with these impairments, an Automatic Repeat Request (ARQ) protocol, which represents a SR version particularly suitable to mobile channel characteristics has been considered. A performance analysis of this SR version, through a simulations campaign aimed to the evaluation of throughput and delay measures, is presented in comparison with those of other SR approaches. The results of the analysis show how an accurate design of lower layers can determine an appreciable efficiency gain

Vehicular communications could be exploited for energy management of vehicles. We propose a system which provides that a vehicle estimates its future speed profile gathering status messages broadcasted by the surrounding vehicles and/or the infrastructure and inputting them in a traffic simulator used as a predictor. The system has been validated by simulation considering an urban scenario inspired to the Ecotekne campus at the University of Salento and a Manhattan scenario, very challenging in relation to the prediction of the speed profile. Simulation results have shown that the prediction error is quite low for the first scenario. In the Manhattan scenario, the error is quite high in case each vehicle limits itself to send messages only to its neighbours and does not transmit the information regarding its route. However, the error can be significantly reduced if route information is broadcasted and the infrastructure relays the messages transmitted by vehicles. The proposed system has been tested in the Ecotekne campus.

This paper proposes a novel algorithm which enables an ARQ protocol defined for IEEE 802.16e to vary the packet size depending on wireless channel behaviour. The algorithm adopts an analytical approach for dynamically evaluating the optimal packet size. The latter is derived from an expression of the ARQ protocol efficiency, obtained by exploiting a finite-state Markov error model which also considers Adaptive Modulation/Coding. The effectiveness of the designed algorithm in improving TCP performance has been evaluated.