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Mega-events imply several city transformations at different scales that could be challenging to be identified and documented. The impacts of such events like Universal Exhibitions are difficult to be identified and tracked in space and over a long period of time. This paper discusses the use of open-source geospatial technologies as innovative tools in support of urban planning and management of digital cities, analysing in particular the case of an international exhibition in the urban landscape. A GIS-based approach is used to design a spatially enabled database, which is essential for implementing advanced analytics in modern smart cities. The pilot project proposes the design and implementation of such georeferenced database for monitoring the urban transformations of the area used for Expo 2015 Milano (Italy). The potential of GIS environment in the consultation process, which allows to obtain different interactive views and to make selections and queries of the data, is explored. The paper also discusses the possibility of publishing such prototype on a shared platform, allowing a larger non-technical audience to follow the urban evolution of the area in a diachronic perspective.

Abstract We assess the performance of different break detection methods on three sets of benchmark data sets, each consisting of 120 daily time series of integrated water vapor differences. These differences are generated from the Global Positioning System (GPS) measurements at 120 sites worldwide, and the numerical weather prediction reanalysis (ERA‐Interim) integrated water vapor output, which serves as the reference series here. The benchmark includes homogeneous and inhomogeneous sections with added nonclimatic shifts (breaks) in the latter. Three different variants of the benchmark time series are produced, with increasing complexity, by adding autoregressive noise of the first order to the white noise model and the periodic behavior and consecutively by adding gaps and allowing nonclimatic trends. The purpose of this “complex experiment” is to examine the performance of break detection methods in a more realistic case when the reference series are not homogeneous. We evaluate the performance of break detection methods with skill scores, centered root mean square errors (CRMSE), and trend differences relative to the trends of the homogeneous series. We found that most methods underestimate the number of breaks and have a significant number of false detections. Despite this, the degree of CRMSE reduction is significant (roughly between 40% and 80%) in the easy to moderate experiments, with the ratio of trend bias reduction is even exceeding the 90% of the raw data error. For the complex experiment, the improvement ranges between 15% and 35% with respect to the raw data, both in terms of RMSE and trend estimations.

Abstract  European geodetic very long baseline interferometry (VLBI) sessions (also known as EUROPE sessions) have been carried out on a regular basis for the past 15 years to study relative crustal motions within Europe. These sessions are based on observations of extragalactic radio sources, which serve as distant fiducial marks to establish an accurate and stable celestial reference frame for long-term geodetic measurements. The radio sources, however, are not always point-like on milliarcsecond scales, as VLBI imaging has revealed. In this work, we quantify the magnitude of the expected effect of intrinsic source structure on geodetic bandwidth synthesis delay VLBI measurements for a subset of 14 sources regularly observed during the EUROPE sessions. These sources have been imaged at both X-band (8.4 GHz) and S-band (2.3 GHz) based on dedicated observations acquired with the European VLBI Network (EVN) in November 1996. The results of this calculation indicate that the reference source 0457퍮 causes significant structural effects in measurements obtained on European VLBI baselines (about 10 picoseconds on average), whereas most of the other sources produce effects that are only occasionally larger than a few picoseconds. Applying the derived source structure models to the data of the EUROPE5-96 session carried out at the same epoch as the EVN experiment shows no noticeable changes in the estimated VLBI station locations. [ABSTRACT FROM AUTHOR]

In recent years, the measurement of dam displacements has benefited from a great improvement of existing technology, which has allowed a higher degree of automation. This has led to data collection with an improved temporal and spatial resolution. Robotic total stations and GNSS (Global Navigation Satellite System) techniques, often in an integrated manner, may provide efficient solutions for measuring 3D displacements on precise locations on the outer surfaces of dams. On the other hand, remote-sensing techniques, such as terrestrial laser scanning, ground-based SAR (synthetic aperture radar) and satellite differential interferometric SAR offer the chance to extend the observed region to a large portion of a structure and its surrounding areas, integrating the information that is usually provided in a limited number of in-situ control points. The design and implementation of integrated monitoring systems have been revealed as a strategic solution to analyze different situations in a spatial and temporal context. Research devoted to the optimization of data processing tools has evolved with the aim of improving the accuracy and reliability of the measured deformations. The analysis of the observed data for the interpretation and prediction of dam deformations under external loads has been largely investigated on the basis of purely statistical or deterministic methods. The latter may integrate observation from geodetic, remote-sensing and geotechnical/structural sensors with mechanical models of the dam structure. In this paper, a review of the available technologies for dam deformation monitoring is provided, including those sensors that are already applied in routinary operations and some experimental solutions. The aim was to support people who are working in this field to have a complete view of existing solutions, as well as to understand future directions and trends.

Global Navigation Satellite Systems (GNSS) receivers are nowadays commonly used in monitoring applications, e.g., in estimating crustal and infrastructure displacements. This is basically due to the recent improvements in GNSS instruments and methodologies that allow high-precision positioning, 24 h availability and semiautomatic data processing. In this paper, GNSS-estimated displacements on a dam structure have been analyzed and compared with pendulum data. This study has been carried out for the Eleonora D'Arborea (Cantoniera) dam, which is in Sardinia. Time series of pendulum and GNSS over a time span of 2.5 years have been aligned so as to be comparable. Analytical models fitting these time series have been estimated and compared. Those models were able to properly fit pendulum data and GNSS data, with standard deviation of residuals smaller than one millimeter. These encouraging results led to the conclusion that GNSS technique can be profitably applied to dam monitoring allowing a denser description, both in space and time, of the dam displacements than the one based on pendulum observations., Competing Interests: The authors declare no conflict of interest.

Weights associated with the EuroQol 5-Dimension 3-Level (EQ-5D-3L) instrument represent preferences for health states elicited from general population's samples. Weights have not been calculated for every country; however, empirical research shows that cross-country differences exist. This empirical study aims at investigating the impact of recently developed Italian weights in comparison with UK and US scores on health-related utility calculation using a sample of patients with Crohn's disease. The study is based on a survey on health-related quality of life in patients (n=552) affected by active Crohn's disease conducted in Italy from 2012 to 2013. Utilities computed through the Italian algorithm (mean: 0.76; SD: 0.20; median: 0.81) are generally higher than US (mean: 0.69; SD: 0.22; median: 0.77) and UK (mean: 0.57; SD: 0.32; median: 0.69) utilities, except for extremely severe health states where US values outweigh the Italian ones. UK preference weights generate the highest number of negative results. All the three value distributions are left-skewed due to very low scores associated with the most serious health states (ie, three or four levels equal to 3). As expected, despite the tariff set considered, more severe disease (Harvey Bradshaw Index >16) reduces the mean conditional EQ-5D-3L index (P<0.0001). Kendall's rank correlation between EQ Visual Analog Scale score and EQ-5D-3L index is positive (P<0.0001), even though patients tend to value their health-related quality of life more when responding to EQ-5D-3L questions than on EQ Visual Analog Scale. Regardless of the tariff set considered, ordinary least-square results highlight that more severe disease (Harvey Bradshaw Index >16) reduces the mean conditional EQ-5D-3L index (P<0.0001). Results reveal remarkable differences among the three national tariff sets and especially when severe health states occur, suggesting the need for country-specific preference weights when evaluating utilities, which can be problematic since they have not been calculated for every country yet.

Aim: To assess the diagnostic accuracy of the platelet count/spleen diameter ratio for identification of oesophageal varices and/or hypertensive gastropathy in patients with compensated cirrhosis., Methods: Platelet count/spleen diameter ratio was calculated in 87 consecutive patients with compensated cirrhosis. A new cut-off with the highest sensitivity and specificity for the presence/absence of oesophageal varices and/or hypertensive gastropathy was identified. Performance of the platelet count/spleen diameter ratio considering previously reported cut-off values were then tested in our population., Results: A platelet count/spleen diameter ratio <936.4 had the best sensitivity and specificity for the diagnosis of oesophageal varices and for all endoscopic findings of portal hypertension. A value lower than 936.4 allowed identification of 64.5% of patients with oesophageal varices and 66.7% of patients with any sign of portal hypertension; a value higher than 936.4 excluded oesophageal varices in 64.3% of patients and any sign of portal hypertension in 68.6% of patients., Conclusions: In patients with compensated cirrhosis, the platelet count/spleen diameter ratio is not a useful parameter to avoid unnecessary upper endoscopy, independently of the cut-off., (Copyright © 2011 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Background: Prevention of post-operative recurrence has a central role in the management of Crohn's Disease (CD). Many drugs have been evaluated in prospective randomised controlled trials (RCTs) but the results are disappointing. Mesalazine, the drug more extensively investigated, has been shown to be effective for preventing recurrence in the short-term; however, the overall benefit is small and no data are available on the long-term effectiveness., Aim: To compare the long-term occurrence of post-operative recurrence in patients who received regular prophylactic treatment with mesalazine with patients who did not receive prophylaxis after the first radical resection for ileo-caecal CD., Patients and Methods: The records of 216 patients with ileo-caecal CD at their first resection were reviewed: 146 patients (67.6%) received post-operative prophylaxis with mesalazine while 70 patients (32.4%) received no prophylaxis. Allocation of patients in the two groups was determined by patients' preferences and by different policies in the post-operative prophylactic approach. The mean follow-up after surgery was 153.7 months (range 12-544). The co-primary endpoints were post-operative clinical and surgical recurrence., Statistical Analysis: Kaplan-Meier survival method, Chi-square, Student t-test., Results: The two groups were comparable with regard to gender, age at surgery, smoking habits, pattern of CD (perforating/not perforating), and disease duration before surgery. One year after surgery, a small, not statistically significant, risk reduction in clinical recurrence was observed in mesalazine treated group (-7.6%; 95% CI -18.0% to 2.8%). Within 10 years after surgery, the cumulative probability of clinical recurrence and surgical recurrence were similar in the two groups (Log Rank test p=0.9 and p=0.1 respectively)., Conclusion: Mesalazine prophylaxis is not effective for preventing the long-term post-operative recurrence in ileo-caecal Crohn's disease.

Since gastro-entero-pancreatic endocrine tumors are rare and heterogeneous diseases, their prognosis and long-term survival are not well known. This study aimed at identifying prognostic factors and assessing long-term survival in gastro-entero-pancreatic endocrine tumors. A total of 156 patients enrolled. Prognostic factors were determined by univariate/multivariate analysis; survival rates were assessed by the Kaplan-Meier method. The tumors were non-functioning in 59.6% of patients, and originated from the pancreas in 42.9%. At diagnosis, 64.3% of patients had metastases. The tumors were well differentiated in 89.6% of patients. Ki67 was >2% in 39.6% of patients. Primary tumor size was >3 cm in 49.6% of cases studied. For the univariate analysis, the negative prognostic factors were: pancreatic origin (rate ratio 4.64, P = 0.0002), poorly differentiated tumor (rate ratio 7.70, P = 0.0001), primary tumor size >3 cm (rate ratio 4.26, P = 0.0009), presence of distant metastases (liver: rate ratio 5.88, P = 0.01; distant extra-hepatic: rate ratio 13.41, P = 0.0008). The pancreatic site, the poor degree of differentiation and the distant metastases were confirmed as negative prognostic factors at multivariate analysis. Overall 5-year survival rate was 77.5%. Survival rates differed according to: primary tumor site (62% for pancreatic vs 89.9% for gastrointestinal tract, P = 0.0001) and size (65.7% for >3 cm vs 88.8% for < or = 3 cm, P = 0.0003), degree of differentiation (22% for poor vs 86.8% for good, P < 0.0001), Ki67 (53.5% for > 2% vs 90.1% for < or = 2%, P = 0.003), metastases (96.1, 77, 73.3 and 50.1% for absent, local, liver and distant extra-hepatic metastases respectively), age at diagnosis (85.3% for < or = 50 years vs 70.3% for > 50 years, P = 0.03). Although 64.3% of gastro-entero-pancreatic endocrine tumors present metastases at diagnosis, the 5-year survival rate is 77.5%. Pancreatic site, a poor degree of tumor cell differentiation and distant extra-hepatic metastases are the major negative prognostic factors.