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Maurizio Sessa,1,* Claudia Rossi,2,* Annamaria Mascolo,1 Cristina Scavone,1 Gabriella di Mauro,1 Roberto Grassi,2 Liberata Sportiello,1 Salvatore Cappabianca,2 Concetta Rafaniello1 1Section of Pharmacology “L Donatelli”, Department of Experimental Medicine, University of Campania “L Vanvitelli”, Naples, Italy; 2Section of Radiology and Radiotherapy, Department of Clinical and Experimental Medicine “Magrassi-Lanzara”, University of Campania “L Vanvitelli”, Naples, Italy *These authors contributed equally to this work Background and objective: The use of contrast media in Italy has exponentially increased in the past 3 decades. However, it is unknown whether there has been an increase in clinical research evaluating the risks associated with contrast media usage, especially regarding contrast-induced nephropathy. To fill this gap in knowledge, we performed a systematic review.Study eligibility criteria: Meta-analyses, observational studies, and clinical trials assessing contrast media-induced nephropathy as the safety outcome, in which at least one author was affiliated with an Italian university/health care structure, were eligble.Data sources: Ovid MEDLINE, Ovid Embase, Cochrane Methodology Register, and Web of Science were screened.Participants: Men and women exposed to contrast media.Results: In total, 60 original articles were retrieved with an incremental trend between 1990 and 2017. Cohort studies were the most common study design represented. In total, 45 of 60 (75.0%) studies were monocenter studies and 41 of 60 (68.3%) received no funding. In all, 91.7% of studies disclosed no conflicts of interest and 81.7% had no external collaboration. Most of the studies provided a level of evidence of III-2 (32/60; 53.3%) and II (23/60; 38.3%). In total, 50 of 60 studies (83.3%) were published in a scientific journal ranked in the first quartile of their subject area.Conclusion: There was an increased number of studies evaluating contrast-induced nephropathy in Italy during the last three decades. These studies covered procedures to prevent contrast-induced nephropathy or aimed to identify risk factors, biomarkers, and scores, and their related prognosis. Keywords: nephropathy, contrast media, Italy, systematic review, drug safety, adverse drug reaction, pharmacovigilance, post-marketing surveillance

A new algorithm based on differential algebra is proposed to obtain a high-order Taylor expansion of the state-dependent Riccati equation solution. The main advantage of this approach is that the suboptimal solution of a class of nonlinear optimal control problems, characterized by a quadratic cost function and an input-affine plant model, is obtained by a mere evaluation of a polynomial expression, reducing the computational effort due to a well-known algorithm for the state-dependent Riccati equation solution. A relative position tracking and attitude synchronization problem involving docking maneuvering operations between two Earth satellites is investigated. Particularly, two possible docking scenarios are simulated by using a specific platform designed by DLR, German Aerospace Center, Institute of Space Systems to emulate the satellite motion on ground. The experiments show the effectiveness of the proposed differential-algebra-based algorithm and the potential computational benefit when it runs on real hardware. [ABSTRACT FROM AUTHOR]

In recent years, several drought monitoring indexes have found application to describe and compare droughts among different time periods and regions as well as to forecast the evolution of ongoing droughts, in order to select appropriate mitigation measures and policies for water resources management under shortage risk conditions. However, limited efforts have been made to investigate the possibilities of using information conveyed by large-scale climatic indexes to improve the forecasting ability of drought indexes, provided they exert some influence on the climatic variability in a region. The aim of the paper is to develop models for forecasting Palmer Hydrological Drought Index series in Sicily (Italy) based on artificial neural networks, and to extend such models in order to include information from large-scale climatic indexes. First, the influence of North Atlantic Oscillation (NAO) and European Blocking (EB) indexes on Palmer index series, computed on areal monthly precipitation from 1955 until 1999 in Sicily, has been investigated by means of a correlation analysis. Results indicate that NAO and EB series are significantly correlated with Palmer index series for winter and autumn months, with special reference to the last decades. Then, forecasting models based on neural networks have been developed, using different approaches. The comparison between the prediction for winter and autumn months obtained by either including or not including the NAO and EB indexes within the forecasting model indicates some improvements in terms of R2 when NAO and especially EB are considered. A different model behavior has been observed for the spring and summer predictions for which no significant improvements in terms of model predictive capability, due to the introduction of the climatic indexes as input variables, have been observed. [ABSTRACT FROM AUTHOR]

Background: The commonest surgical procedure for management of morbid obesity in Europe is laparoscopic adjustable gastric banding (LAGB), even though laparoscopic vertical banded gastroplasty (LVBG) is still considered to be a gold standard restrictive option in bariatric surgery. A multicenter prospective study was designed to to assess the efficacy of LVBG in terms of weight loss and complication rates for obese patients who have indications for a restrictive procedure.Patients and Methods: Two-hundred morbidly obese patients (84.5% female) with a mean age of 41 years and mean body mass index (BMI) of 43.2 kg/m(2) underwent LVBG as described by MacLean. Five trocars were placed in standard positions as per laparoscopic upper gastrointestinal surgery. A vertical gastric pouch (30 ml) was created with circular (21 or 25mm) and endolinear stapling techniques, enabling definitive separation of the two parts of the stomach. The gastric outlet was calibrated with either a polypropylene mesh (5.5 cm in length and 1cm in width) or a nonadjustable silicone band. The median follow-up period was 30 months (range, 1-72 months).Results: One case had to be converted to open surgery (gastric perforation) and there was one death secondary to peritonitis of unknown etiology. The morbidity rate was 24%, comprising the following complications: gastric outlet stenosis (8%); staple line leak (2.5%); food trapping (1.5%); peritonitis (1%); thrombophlebitis (1.5%); pulmonary embolism (0.5%); and gastroesophageal reflux (9%). The excess weight loss achieved was 56.7% (1 year), 68.3% (2 years), and 65.1% (3 years).Conclusions: Laparoscopic vertical banded gastroplasty is an effective procedure for the surgical management of morbid obesity, especially for patients who present hyperphagia but are unable to manage the constraints of adjustable gastric banding. Laparoscopic vertical banded gastroplasty is safe, as demonstrated by an acceptable complication rate, of which gastric outlet stenosis, staple line leakage, and gastroesophageal reflux predominate. [ABSTRACT FROM AUTHOR]

Unlike other natural disasters, drought events evolve slowly in time and their impacts generally span a long period of time. Such features do make possible a more effective drought mitigation of the most adverse effects, provided a timely monitoring of an incoming drought is available. Among the several proposed drought monitoring indices, the Standardized Precipitation Index (SPI) has found widespread application for describing and comparing droughts among different time periods and regions with different climatic conditions. However, limited efforts have been made to analyze the role of the SPI for drought forecasting. The aim of the paper is to provide two methodologies for the seasonal forecasting of SPI, under the hypothesis of uncorrelated and normally distributed monthly precipitation aggregated at various time scales k. In the first methodology, the auto-covariance matrix of SPI values is analytically derived, as a function of the statistics of the underlying monthly precipitation process, in order to compute the transition probabilities from a current drought condition to another in the future. The proposed analytical approach appears particularly valuable from a practical stand point in light of the difficulties of applying a frequency approach due to the limited number of transitions generally observed even on relatively long SPI records. Also, an analysis of the applicability of a Markov chain model has revealed the inadequacy of such an approach, since it leads to significant errors in the transition probability as shown in the paper. In the second methodology, SPI forecasts at a generic time horizon M are analytically determined, in terms of conditional expectation, as a function of past values of monthly precipitation. Forecasting accuracy is estimated through an expression of the Mean Square Error, which allows one to derive confidence intervals of prediction. Validation of the derived expressions is carried out by comparing theoretical forecasts and observed SPI values by means of a moving window technique. Results seem to confirm the reliability of the proposed methodologies, which therefore can find useful application within a drought monitoring system. [ABSTRACT FROM AUTHOR]

This work analyzes the waves of currents in residential loads, evaluating the effects of attenuation and diversity in the cancellation of harmonics, pondering their influence in the prediction of distortion indexes in a distribution system. Starting from signals of currents registered in laboratory and subsequently treated with Fast Fourier's Transformation, the loads were modeled like sources of fixed currents to be combined and simulated with the "Electromagnetic Transient Program" (EMTP), determining the resulting index of harmonic distortion. With models of nonlinear loads inserted in a distribution system, the diversity and attenuation phenomena were evaluated in the EMTP, in the following stages: connection of identical loads (with equal and different powers) and variations in the impedance parameters of the distribution network. The results found verify the fact that the rejection of such phenomena can cause an overestimation of harmonics in a distribution system. [ABSTRACT FROM PUBLISHER]